How can I migrate my data/apps from one Honeycomb tablet to another? I got myself Honeycomb tablet, but after I used it for a while I've decided that I'd like to get a different one.

How do I transfer all my apps from one tablet to another?

Or, if this is not possible, how I can delete all my data from my old tablet?
Yes if you've previously set your current tablet to back up your data and settings to Google's servers, then during the initial setup of your new tablet you should be given an option to restore your previous settings and data.
The settings that you need to check on your current tablet are in Settings -&gt; Privacy Settings. See below for more info on this from the official Android 3.0 (aka Honeycomb) user's guide:
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Backing up and restoring your data
You can back up your settings and
other data with your Google Account, so if you ever replace your
tablet, you can restore your data on the new one. If you choose to use
this service, your data is backed up automatically.
If you previously
used the backup service with the Google Account you just used to sign
in, you can also choose to restore your settings from your Google
Account to your tablet now.
Important If you want to restore your
settings, you must do that now during setup. You can’t restore data
after setup is complete.
Many kinds of data are backed up, including:

Your Android settings, such as your Wi-Fi networks and passwords, user dictionary, and so on
Many Google application settings, such as your Browser bookmarks
The apps you download from Android Market

Some third-party apps also make use of the backup service, so if you reinstall one,
its settings and data are restored.

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Privacy settings
You use the Privacy settings to manage whether your
settings and other data are backed up to Google servers, using your
Google account. You also use these settings to erase all the data on
your tablet by performing a factory data reset.
Back up my data Check
to back up some of your personal data to Google servers, with your
Google Account. If you replace your tablet, you can restore the data
you’ve backed up, the first time you sign in with your Google Account.
If you check this option, a wide variety of your personal data is
backed up, including your Wi-Fi passwords, Browser bookmarks, a list
of the applications you’ve installed from Market, the words you’ve
added to the user dictionary used by the onscreen keyboard, and most
of the settings that you configure with the Settings application. Some
third-party applications may also take advantage of this feature, so
you can restore your data if you reinstall an application. If you
uncheck this option, you stop backing up your data to your account,
and any existing backups are deleted from Google servers.
Backup
account Displays the Google Account that your settings and other data
are backed up with. This is the account you need to sign into on a new
Android tablet or other device, if you want to restore the settings
from this tablet to that device.
Automatic restore Check this option
to restore settings and other data when you reinstall an application.
This feature requires that you are backing up your data with your
Google Account and that the application is using the backup service.

To wipe your current tablet (after you've ensured that it's been backed up, from the same privacy screen you should also see this option:

Factory data reset Opens a dialog where you can erase all of your
personal data from internal tablet storage, including information
about your Google Account, any other accounts, your system and
application settings, any downloaded applications, as well as your
music, photos, videos, and other files. If you reset the tablet in
this way, the next time you turn on your tablet you’re prompted to
reenter the same kind of information as when you first started
Android.