You have to download the latest gapps which is March 7th
Heres the link:
Goo-inside.me Downloads - Downloading gapps-gb-20110307-signed.zip and I loaded it through the CWM, but i beleve you can grab it through the rom manager, but not sure on that.
EDIT: also i read bad things can happen when restoring system files especially going from Stock, or CM6 to Gingerbread, or any different rom for that mater. Also when restoring apps from Titanium the market wont know there actually installed and wont update them, or even act as if they were installed....Now on Amazons app market I believe your list of installed apps are actually kept on amazon servers, so that wont be to much of an issue....
Now what i have done in the past, but dont do any more, and wouldn't advise it, is if you restore your apps downloaded from market first, and then restore the market+data, and restart your phone, the market should see your installed apps, and will update them in the future when needing an update...but id only do that if you really really, dont want to re download all the apps...and not even sure if it would work going from Froyo-to-Gingerbread....personally me, I actually like having a fresh system, and apps installed from market, and then I use Titanium to restore my data on the games, and such.