Compared to...

Studio scene comparison (RAW)

This is our standard studio scene comparison shot taken from exactly the same tripod position. Lighting: daylight simulation, >98% CRI. Crops are 100%. Ambient temperature was approximately 22°C (~72°F).

Olympus E-P1 (RAW) vs. Panasonic G1 (RAW)

Olympus E-P1
Panasonic DMC-G1
8.9 MB JPEG (4032 x 3024)
3.8 MB JPEG (4000 x 3000)

No surprises to see that the Panasonic G1 (which has a very closely related sensor, though probably not the same low-pass filter) produces results that are similar to those of the E-P1. Panasonic has traditionally fitted extremely weak low-pass (anti-aliasing) filters to its cameras, with the DMC-L10 being notrious for capturing absurd levels of detail but with a greater-than-usual risk of moiré interference patterns appearing. Olympus went in the other direction and, for at least one generation of its cameras, applied one of the strongest filters we'd seen. In these examples you can see that, while some of that philosophical difference remains - with the G1 producing significantly sharper output - the difference is not nearly as great as it used to be (and may be exacerbated slightly by ACR's rendering of the E-P1's files).

The E-P1 may not go to the same extreme as the G1 but its low-pass filter seems to be greatly improved over The E-420 and E-520, offering similar levels of fine detail as similarly-priced DSLRs from other makers.