I've been shooting with Donna's Rebel T2i a lot lately and one of the things I noticed is regardless of the shot I never noticed any blinkies when reviewing images on the rear display. This seemed odd to me so I started doing some experimenting by deliberately increaing exposure compensation to cause the highlights to be blownout but even when the image was almost completely white nothing blinked. The image blow shows the view of the screen. Observe how exposure compensation is set to +1 stop yet there's no blinkies.
I searched through all the menus, the manual, and did some Google searches and never could find a setting for the camera to show me blinkies. I finally gave up and called Canon Support and within a matter of minutes I figured out what was going on. Seems the T2i doesn't show blinkies when viewing images in full screen mode which really sucks, IMO since even my old Rebel XT would show me blinkies when reviewing images.
If you want to see blinkies you have to use one of the different view modes as shown below. While it's nice to see the histogram and additional information I really don't like that the image is so small but at least I can see the blinkies now. If you look closely you can see the reflection of my Canon PowerShot D10 in the image.
I guess I really shouldn't complain too much about this because Donna primarly shoots with the T2i and I shoot with a 7D and it does show me blinkies when reviewing the images.
So there you have it. If you were like me and having a hard time figuring out how to check for blinkies on a T2i now you know.