Pathauto and taxonomy I use the default taxonomy view (with default path: /taxonomy/term/%) to display videos that have been categorized at the time of their upload. The viewer has access to an exposed filter that allows him to select like 10, 30 or 40 video thumbnails per page (default is 10.)

The Pathauto taxonomy pattern for all video paths is:
[term:vocabulary]/[term:name]
Token is enabled.

The url of the landing page is correctly displayed www.example.com/videos/sports when the vocabulary "videos" and the term "sports" are selected through a menu.

But if, on that same page, I select to view 30 video thumbnails per page instead of 10, the url changes to:

www.example.com/taxonomy/term/1989/0?items_per_page=30

This appears normal since the the view path is /taxonomy/term. The content displayed is correct, but the page theming is totally out of wack.

How do I keep the url at www.example.com/videos/sports/0?items_per_page=30 ?

Shouldn't Pathauto handle this?
Again, I will give my own answer here:

After reading about tokens, pathauto and views, it appears that exposed filters DO NOT work with path (dixit Merlinofchaos in https://drupal.org/node/1257952#comment-4898854 .) So what I am experiencing is normal.

However, views have a "Use Ajax" option that is specifically there for exposed filters. Enabling it solves the issue and keep the url clean (without the *0?items_per_page=30* part.)

It does so because ajax does not refresh the page, so the url remains the same (www.example.com/videos/sports in this case.)   :)