I recently stumbled upon this, Olympus' newest DSLR on my favorite source for photo info but found it uncharacteristically lacking. Search engine results and preliminary reviews almost make me want to take back what I said about the E-3. Almost... I'd probably still go for the E-3, however, I'm sure I'd also jump at the chance to hold / own / use the Olympus E-30.
Announced November of last year, one wonders where the E-30 fit in Olympus' scheme of things. Well, supposedly it is positioning itself between the rugged Professional E-3 and the less than pro E-520. It's not as rugged, nor weather sealed as the E-3 (which used magnesium alloy, versus the E-30's structural plastic), and weighs in just midway between the two models. Dimensions-wise however it shares the E-3's girth, if only to be slightly shorter by 10mm. Additionally a newly designed viewfinder [penta]prism makes it lighter than the pro, but at the same time gives it a better view than the 520.
The newest camera from Oly also bosts 12.3 megapixels of resolutional goodness. While this may potentially mean more noise, as more pixels would be crammed into the same size sensor space, Olympus promises that noise levels will be more like the previous generation of sensors thanks to better microlens and photo diode design.
Like the E-3, the E-30 possesses a rotating LCD display, however Olympus decided to give it a larger 2.7 inch screen. Like the E-30, it also uses an 11 point AF sysetm but throws in the Face Detection feature found in the E-520.
Aside from the above mentioned features, the E-30 posseses a digital leveling feature, which lets you know how much roll / pitch you've to fix to help level your camera. Helpful for people who'd like to get their horizons perfectly straight, but otherwise also perfectly superfluous, in my opinion anyway. :)
For a more complete review, do check out imaging resource.