If you're coming from the Digital Rebel XSi / 450D to the T1i, you'll notice that Canon has removed the dedicated button for changing metering modes (one of the following: Evaluative metering, Partial metering, Spot metering, Center-weighted average metering).

Pete4 says:

Metering mode button is gone but simple enough: press SET and you can access most functions by scrolling around, once metering mode is active pressing set again will give you menu to choose the mode. After that if you going back to the menus in the future press SET twice and you're in metering mode menu. I don't change metering mode that often and don't miss separate button for it at all.

According to Macro, selection of a metering mode isn't on the list of functions that can be directly accessible by pressing the SET button:

The SET button options do not include metering mode.
0: Quick control screen
1: Image quality
2: Flash exposure comp.
3: LCD monitor On/Off
4: Menu display
5: Disabled

Canon XSi / 450D vs Sony A230: Build Quality – dougas:

I was so disappointed by the build quality as well, it felt really cheap and nasty. I picked up a Canon 450D which was next to it and it felt so much better, and thats the 450D which we all know is a plastic built to a price camera.