Here's my experience of it on crop.
When I first started, the first 5 weddings were pro bono, so I didn't have to worry about contracts or consideration or even insurance. I only had 1 body and it was the 30D and the lens I used the majority of the time was the Tamron 17-50.
I also had in the bag:
50/1.8 (focus sucks in low light)
550EX Flash
70-200 2.8 IS (rented for 2 of the weddings), hardly used.
That's it. If you are quick on your feet and anticipate the scene you can get away with adding just the 17-50 in your bag. Go pick up a 30/40D secondhand for about £200 and use it as a back up and bob's your uncle. In fact, when I moved to the 5D, I used 24-70 for half a dozen weddings before I got a 35/1.4, then I got a 135/L, then a 85L. At the beginning my 24-70 (along with my 50/1.4) are perfectly capable combo. Use the zoom for the versatility and the 50 when you want that bokeh or extra 2 stops. I also had a 16-35 for the wide stuff. These days I don't take my 70-200 with me, the longest lens in the bag is a 135L and even that only get used if I am forced to be in a certain position away from the action The rest of the time I use my feet.
7D + 17-50/2.8 = done.
Although these days, I can do a whole wedding with just a 35/85 prime lens combo.
One time, my 24-70 had an Error 99 at 11am mid shoot, for the next 13 hours I used the 16-35/50/85.
And remember to have lots of cards, lots.