Forget the Classifieds tab, you now have to go to "Classifieds" under the Forum tab.
Who knows? You also can't post pictures of your items that you are trying to sell. What's up with that?
While the current Photo Gallery does not display the Best Fit URL as it has in the past, you can still drag-and-drop photos from your Albums into your posts.
The following was drag-and-dropped from my personal Album.
As for the Classifieds section, the replacement Classified application has not yet been chosen or implemented, so a "Classifieds" forum has been created to fill the role until a new Classifieds app can be implemented. The old Classifieds app was not compatible with the new version of vBulletin this site now runs, so there was no way to carry forward that service without loss or interruption since no clear upgrade path existed.
The site you are seeing today is not the final site. It was a choice between allowing you all in when the site was 90% complete, or make everyone wait several more weeks until it was 99% -- which would you have preferred? ;-)
The new version of the classifieds is currently being tested. Until it is ready for release you can use the Classifieds forum as already has been mentioned.