Firefox 1.5.0.11 & 2.0.0.3 have been released and fix some regressions that appeared in Firefox 1.5.0.10 & 2.0.0.2

The main regression it fixes is with the password manager whereby passwords may not appear if you have multiple accounts on a particular site.

You can get then either from the built-in update system or:
Firefox 2.0.0.3 - http://www.mozilla.com/en-US/firefox/all.html
Firefox 1.5.0.11 - http://www.mozilla.com/en-US/firefox/all-older.html

Another unrelated matter that may be of interest. When you search for updates to extensions and themes you may recently have found no updates available. This is due to changes that are being made at the Mozilla Add-ons site. The current database that stores details of add-ons on that site is being replaced. The last updates on that site were made around 8th March and at that time the database was migrated to a new system in preparation for the launch. The new re-designed site is due to be launched on 22nd March, so if you check for updated add-ons after that date you may find updates for your extensions and themes.