user175: My question may seem a little simple, but most events regarding anime and manga are chronological.
Would asking a question about the first couple arcs of an anime or manga without the use of the spoiler box be spoiling?   Can we assume that people already watched the arcs due to how long ago the content was released?
For example, would it be spoiling if I asked the following question not in a spoiler box:

 In Sanji's arc of One Piece, Why did Nami steal Going Merry?


user111: This is a tricky question. First let's see what definitely are spoilers.

If the question is based on anime, using the information from manga chapters that were not yet made into anime episodes is totally a spoiler. I believe that along with including it in a spoiler box, it's a good idea to explicitly state that it comes from manga that has not yet been screened. 
If the question is about the events in a particular episode/chapter, data colected from much later chapters is a spoiler. For example, if the question is "Why did X happen in episode Y?", and the answer is "Because in episode X+100 it's explained, that...". The part after "that" should be put into the spoiler box.

Now, to more controversial examples.

Information about key events, especially about character deaths, should almost always be put into the spoiler box. The exception is if the question is about a specific chapter/episode, and the events happen before that episode. In that case people who haven't watched/read up to this episode/chapter will not open the question in the first place.
I believe that any cross-over information should also be put into the box. For example, if the question is "Why X", and the answer is "Well, do you remember how in anime YY, character ZZ died in episode 75? It's pretty much the same here". Such information should be put into the box. It's frustraiting to come into a question about something you have watched long ago, and be spoiled on the events of another title that you are watching now. 

And finally, every other piece of information that you think might be a spoiler for other people that come by your question/answer, should be put into the box. Don't be too worried: if you put an unnecessary box, or forget to put something important into it, other users will most likely edit your question/answer, or leave a comment for you. Remember, it's absolutely nothing bad including information that is hardly (or not at all) a spoiler into the spoiler box; it doesn't hurt anyone.
So, basically, using common sense is enough to determine whether you should use the box or not.

user27: I argue that anything later than the scope of the question is considered a spoiler.
For instance, if the question is about the Chuunin Exams arc in Naruto, an answer from an earlier arc (such as the Zabuza arc) shouldn't be marked as spoilers.
If the answer is from a later arc (Rescuing Sasuke, for example), those details should be marked as spoilers.

Aside from that, make sure your title isn't spoilerish, and if it is, generalize it to make it good for reading:
How did Character X break out of Edo Tensei?
Is problematic if Character X broke out of Edo Tensei very recently in the manga, which may spoil it for anime viewers.
How can Edo Tensei be broken?
Is better. It only implies that Edo Tensei can be broken, which isn't very spoilerific. Inside of the questions, also in spoiler tags, should be the detailed question, with some introduction message:
Warning! The following contains spoiler for Naruto anime viewers!

 Spoiler content here

That's my perspective on how we should be treating spoilers.

175: <p>My question may seem a little simple, but most events regarding anime and manga are chronological.</p>

<p>Would asking a question about the first couple arcs of an anime or manga without the use of the spoiler box be spoiling?   Can we assume that people already watched the arcs due to how long ago the content was released?</p>

<p>For example, would it be spoiling if I asked the following question <strong>not</strong> in a spoiler box:</p>

<blockquote class="spoiler">
  <p> In Sanji's arc of One Piece, Why did Nami steal Going Merry?</p>
</blockquote>
 111: <p>This is a tricky question. First let's see what <em>definitely</em> are spoilers.</p>

<ul>
<li><p>If the question is based on anime, using the information from manga chapters that were not yet made into anime episodes is totally a spoiler. I believe that along with including it in a spoiler box, it's a good idea to explicitly state that it comes from manga that has not yet been screened. </p></li>
<li><p>If the question is about the events in a particular episode/chapter, data colected from much later chapters is a spoiler. For example, if the question is "Why did X happen in episode Y?", and the answer is "Because in episode X+100 it's explained, that...". The part after "that" should be put into the spoiler box.</p></li>
</ul>

<p>Now, to more controversial examples.</p>

<ul>
<li><p>Information about key events, <em>especially</em> about character deaths, should almost always be put into the spoiler box. The exception is if the question is about a specific chapter/episode, and the events happen before that episode. In that case people who haven't watched/read up to this episode/chapter will not open the question in the first place.</p></li>
<li><p>I believe that any cross-over information should also be put into the box. For example, if the question is "Why X", and the answer is "Well, do you remember how in anime YY, character ZZ died in episode 75? It's pretty much the same here". Such information should be put into the box. It's frustraiting to come into a question about something you have watched long ago, and be spoiled on the events of another title that you are watching now. </p></li>
</ul>

<p>And finally, every other piece of information that <em>you</em> think might be a spoiler for other people that come by your question/answer, should be put into the box. Don't be too worried: if you put an unnecessary box, or forget to put something important into it, other users will most likely edit your question/answer, or leave a comment for you. Remember, it's absolutely nothing bad including information that is hardly (or not at all) a spoiler into the spoiler box; it doesn't hurt anyone.</p>

<p>So, basically, using common sense is enough to determine whether you should use the box or not.</p>
 27: <p>I argue that anything <strong>later than the scope of the question</strong> is considered a spoiler.</p>
<p>For instance, if the question is about the Chuunin Exams arc in Naruto, an answer from an earlier arc (such as the Zabuza arc) shouldn't be marked as spoilers.</p>
<p>If the answer is from a later arc (Rescuing Sasuke, for example), those details should be marked as spoilers.</p>
<hr />
<p>Aside from that, make sure your title isn't spoilerish, and if it is, generalize it to make it good for reading:</p>
<h1>How did Character X break out of Edo Tensei?</h1>
<p>Is problematic if Character X broke out of Edo Tensei very recently in the manga, which may spoil it for anime viewers.</p>
<h1>How can Edo Tensei be broken?</h1>
<p>Is better. It only implies that Edo Tensei can be broken, which isn't very spoilerific. Inside of the questions, <em>also in spoiler tags</em>, should be the detailed question, with some introduction message:</p>
<h3>Warning! The following contains spoiler for Naruto anime viewers!</h3>
<blockquote class="spoiler">
<p> Spoiler content here</p>
</blockquote>
<p>That's my perspective on how we should be treating spoilers.</p>
