Show what comes next?

For a couple months now I've been thinking about buying a new 40D, a studio light set or the 17-55 2.8 IS. The thing is I can only get one right now and will have to wait for the others. I have been going back and forth for too long and I'm about to pass out!

The thing is, I have my first official wedding coming up in December (I've assisted many) and all I have is the XTi and the 28-135, 18-55 and 50 1.4. I figured I could rent the lenses if I needed to for the wedding and I hear everyone say that glass is better than a body. And I'll need some lights for the formal shots at the wedding too.

What do you guys think? What should come first? Second?

Rent the 17-55 IS, a second body, a 70-200 f/2.8 IS, and 2 flashes.

Normally I'd say, glass first, but you're going to need a 2nd body before the wedding, so keep the XTi. If you aren't already shooting RAW, think of it as upgrading the XTi.
A max jpg from my 20D is 2,754 KB. The exact same shot with the jpg extracted from RAW is 4,315 KB which is 1.57X larger. Why throw those extra bits away?
Some excellent comparison images: RAW vs. JPEG - the real story

Sounds good. Some info on it.

You might not need it with the 50 f/1.4 you have. Depends on how you like to work.

If you have a budget crunch, I don't think you could go too far wrong by buying a used 20D. Then when your gear has paid for itself, you could keep that & upgrade the XTi.

Perryge, so you're saying to just rent everything?

PhotosGuy, yes I am already shooting RAW and wouldn't shoot any other way! I agree that renting the lenses would be a good thing to do (for which ever ones I don't have).

Should I get strobes or a couple 580's? The cost is about the same so you can't really say much there, but the flashes win in portability. Any other thoughts?

What you get isn't as important as learning how to use it/them. I use cheap, manual strobes, which have worked for decades. They only do what I tell them to do.
Simple "every-day-emergency" location lighting
So I test & tell them what to do at given distances & they never let me down.

See post #3