Howdy All,
After numerous phone calls to both Canon and Kingston, along with testing various SDHC cards under the same conditions in multiple T2i bodies, I've come to the conclusion that the Kingston SD6/8GB-U (Class 6 Ultimate 133X) cards will take 24x (72 seconds vs. 3 seconds) longer to do a T2i in-camera, low-level format when compared to many other SDHC brands, including Sandisk Extreme III Class 6 cards. This formatting time issue doesn't seem to occur in other manufacturer's products that I tried. I finally visited the Kingston Technology manufacturing location in Fountain Valley, CA today. They ran various tests with my T2i and numerous Kingston cards. Their conclusion was that those two prodcucs just don't like to do a normally fast low-level format 
. All of the cards did fine with a quick format, transferring files, video capture, etc.
For some users this boils down to just an annoyance when it comes time to do a low-level format, but if you are an ARPA (anal-retentive, painful analytic) like me, it bugs me to no end
. The people at Kingston were great about the whole thing. Their phone support dug deep into the design details and the engineers who evaluated the interaction of my T2i and the cards were thorough.
The older Kingston SD6/8GB (non-U) formats in 11 seconds which doesn't bug me as much as the 72 second format time. Both my Sandisk and my Hoodman Class 6 cards format in 3 seconds doing low-level pass. Doing a quick format of any of these cards ranged from 1.5 sec to 3 seconds.
Kingston gladly refunded my purchase price ("check is in the mail") and I left them with the card.
I was tempted to point the finger at Canon but since the memory is on the cheaper end of the stick I went that direction.
