I was in Rome and Sorrento last year. My 10-22mm got a lot of use. My 17-55, less so. But, I remember thinking that I could have gotten by with the 17-55, if I didn't have the wide angle. It depends on what kind of shots you want to take.
If you take the 50mm and a wide angle, you will be happy.
I also took an 85mm prime, that I hardly used.
I'm currently more of a budget guy, having just graduated from college not too long ago, so I haven't started investing too heavily in lenses yet, as photography is a new hobby of mine.
I'm working with 50mm 1.4, 18-55 IS kit lens, and 70-300 IS on my 1.6x XSi/450d. I don't know how much more I can afford right now, but I'm making the Venice-> Florence/Pisa-> Rome trip in April.
The one place I feel I'm lacking is the wide end of the spectrum. (clearly) For one, I'm debating if I should even bring my 70-300--It's a heavy lens to be carrying around, and I don't see myself taking too many shots that utilize that range.
At this point, I'm debating if I should rent a lens for the 2 week trip, or just stick with what I have and hope I don't need wider. The 10-22 seems to be pretty expensive (for my current budget) but it also seems like a very well recommended lens, and fits the exact range I'm lacking right now.
I'm wondering if a) people see the utility for the 70-300 on a trip like this,
and b) if the 10-22 is worth shelling out for at the current Amazon price, or if I should rent it to see how much use I get out of it on a two week trip before committing to it.
Some great discussion here as well as good photo samples. It's getting me more worked up about going on my trip in just 2 months!
Edit: A third question! Is it worthwhile to bring both the standard 18-55 IS kit lens AND the 50mm 1.4? Obviously the quality is superior on the 1.4, but I need some kind of walkaround lens, and being stuck at 50 (x1.6) doesn't seem like the best idea for a trip like this. Sorry for the huge post--I'm just excited and don't want to blow it--I won't be going back for quite a long time, after this.