Things I would absolutely like to add:
I'm always looking for more quality sites to add - just added eBay Motors, which should be next...?
The most important thing is to make the site useful to you! So please, send me your suggestions!
Not much more to say here.. except that their stuff was somewhat more challenging than the other sites'. Except CarsDirect, but that's just because CarsDirect is oh-so-broken. ;)
The lists of makes an models are somewhat more logical now, and (after a fair bit of work I must say), CarsDirect should be working much better.
The site now remembers the settings from your most recent search, so no need to enter them again each time.
You can now manually close and refresh tabs, as well as open more than one tab for each site.
I also thought it would be fun to throw in multi-purpose tabs, so you can now open additional tabs to check the blue book, your email, etc. 
The beta version of the site is now up and running! Time to go buy a car!