The fountain view rooms are a nice touch but I wouldn't pay much extra for them. $20 sounds right. Unlike the Bellagio fountain view rooms, you are viewing from quite a distance and you can't play the soundtrack over the tv.
So, while you may glance out at them from time to time, you aren't likely to spend much time actively watching like you might at Bellagio.

Not sure about free upgrades, but join mlife and sign up for e-mail, I've gotten some great offers this way, even without gambling. It's a very nice hotel. Not a spectacular resort like some of the high-end Vegas properties, but spacious and quiet. The main downside (depending on what time of year you go) is a small pool that was clearly designed for condo residents and not a hotel.