Since the phone is fixed focus, there shouldn't be any significant lag (focusing is what causes lag in camera phones). However, camera phones aren't as fast as dedicated cameras and a 1/4 to 1/2 second lag isn't uncommon. My Eternity is pretty fast for a camera phone though, and I'd say the delay is 1/4 second or less when shooting a photo using the auto settings. There is a delay while the phone saves images to the microSD card (again, all phones have this), and it's faster to save to internal memory. But that's independent of the shutter time.
-------------------- Lisa Gade Editor in Chief, MobileTechReview