Need help...Wedding Photography

Well...thanks all for your wonderful suggestions. Just a little more info about what I'm up against:

1) There will be a reception only (Actual wedding took place today)
2) The reception is tomorrow night. Not a lot of time.

3) Since I've done this before (normal weddings) I really am not afraid to push the ISO as much as I can get away with but for this I will try the ISO 400 setting first as suggested
4) I will be able to WB the location before shooting

5) I will probably bump up the flash (I've had success at +1 settings) but I know I will have to be careful not to blow out highlights from white clothing
6) I do plan to use the 50mm 1.8 quite a bit

7) I probably will be able to get the Bride/Groom into a well lit location at the location in order to use the 24-120 f4.
8) I will try to borrow a 24-70 2.8 from camera club friends tomorrow
9) No professionals will be there! I'm it!!!!!

Thanks all. I will let you know how it turns out.