The Olympus E-3 retains the universal 4/3rds system. There's a whole host of lenses to chose from to add some serious icing to your existing Olympus E3 cake. This compatibility is not just limited to Olympus ZUIKO DIGITAL lenses however - take your pick from recent additions from Panasonic (via the LUMIX DMC-L10 DSLR), amid a range of Sigma glass.
The particular Olympus ZUIKO DIGITAL 14-54mm (28-108mm equiv) f/2.8-f/3.5 lens that comes with this kit is a real joy. Focusing isn't at record-breaking speeds, but from lens to image the quality is held superbly. Hats off to Olympus, as many manufacturer's kit lenses really don't bring the full potential of the camera body out. In fairness, this is a 'High Grade' or 'Pro' lens ; there's and a 'Super High Grade' or 'Top Pro' 14-35 f/2 and a 'Standard' grade 14-42 f/3.5-5.6 covering roughly the same zoom range. Read the whole article here