Gingerbread has not been officially released for the Desire yet. Who knows.
However, I flashed CyanogenMod7 V7.0.0-RC3 with absolutely no issues. It uses Gingerbread. Overall preformance increase about 30% or more from Stock HTC 2.2.
Use leedroid 3.0.2,contains gingerbread,sense 2.1,and is very stable to run,just search for it over @ xda,only problem is the compass right now,which doesn't work properly (gps works fine though)
Sent from my HTC Desire using Tapatalk-Install Dropbox through my Referral Link http://db.tt/mPFv6q2 to get an additional 250 MB for free