I've handled quite a few Novas and have come darned close to buying one on several occasions. Never could quite bring myself to do it, though.
PROS: Affordable, lightweight, simple design (I like the punch designed into the mag cap), seems fairly robust, handles shells up to 3 1/2", ergos for me are decent, comes in camo and black.
CONS: Forearms typically rattle a lot, Due to the stock design and the recoil pad they don't readily allow a custom fit, "funky" looks, fewer (and costlier) aftermarket parts than the 870, only comes in camo and black, and finally... horrible triggers.
It's mainly the last thing which has prevented me from getting one. Last Fall, I spent quite a bit of time trying different Novas, trying to find one with an acceptable trigger. It didn't happen. I ended up getting an 870 Supermag.
All that being said, I know a few folks who shoot them and like them a lot.