I got my dRebel a couple of months ago w/the kit lens and it ended up to be about $650 (there was a $100 canon rebate at the time.). Just last week I did go ahead and buy the 50mm 1.8 for about $70 - figure I couldn't go wrong for that price.
I love the camera and the lens and will never regret it...but here are a few thoughts...
The dRebel w/kit lens has a smaller shooting area (lol - have no idea what that's called) compared to my Canon PowerShot. Although I love the lower f stop of my 1.8, it seems to have an even smaller 'shooting area' and you can not zoom the lens in and out like with the kit lens. I'm sure I'll get used to both of those things

But the 1.8 does shoot much better in low light - the reason I got it...for the indoor shots so I don't have to use flash.
So I love them, but may have to get another wide-angle lens if I plan to do lots of family/big group photos if I don't want to keep backing up to take the pixs.
Also, I noticed that w/the 50mm 1.8, I can't be too close to the subject either.