It is supposed to be a pretty good lens. It's not very wide on a crop body, so it is considered a normal to short telephoto zoom. Eventually you may want a wider lens, but the 28-135 is a pretty good lens in general and should cover you for most situations.
Are you planning on buying this as part of a kit, or separately, and what camera would you be using?
I have it on an XTi and am very please with it. I has a good range for me and is the lens that gets left on my camera the most. It is an excellent walking around lens. It does leave a little wanting in terms of wide angle, but I have an 18-55 and that hardly gets any use. I tend to prefer the extra range over the 17-85 and sacrifice some wide angle, but its all personal preference.