Olympus Zuiko Digital ED 12-60mm f2.8-4.0 SWD lens

Pros: real wide angel (24mm. equiv); very sensible tele (120mm equiv); sharp over the whole range; low/unnoticable distortion; reasonbly fast (f2.8-4.0)

Cons: only minor points that would be solved in a lens twice as expensive

Summary: Great lens for your basic needs: real wide angle (24mm equiv) till 120mm (equiv) tele, so buildings and protraits and landscapes one can do with this one lens -- and one *can*, because distortion is unnoticable, the lens is sufficiently fast, and already sharp at maximum apperure, thus making good portraits with shallow depth of view possible.
There is slight corner softness at 12mm, which disappears two stops down; there is also slight vignetting at maximum apperture, which takes also one stop down to disappear (only two stops at 60mm) -- I think that 4/3 lenses, given the smaller image cirkel, should be free of vignetting.
Constant apperture of 2.8 would have been nice, but then there is always something to ask for, and for the price, you really get what you pay for; an excellent photographic tool.