Let me put it this way: with the Canon 5D, when I'm using the 24-105L IS as my standard lens, most of my vacation/travel shots are at 24mm or 28mm. The 7-14 includes these focal length equivalents, and adds the range equivalent between 14mm and 24mm. Shots at the maximum zoom are at 28mm, which produces no more keystoning distortion than an equivalent lens on a full-frame; it's not what I'd call ultra wide. It's only when you get down to near 7mm that you have to pay extra attention to keeping the camera level, and making sure that you don't have a lot of empty space in the foreground--but then the same goes for shots with other lenses. I have the GF1 and the 7-14, 20mm, and 45-200 mm. I like all three lenses, but the 7-14 is probably my favorite.
Bob