Coming from a long list of Logitech mice, the most recent the MX518, I have to say the MXRev is a lot more comfortable, however for me it's also a lot heavier, which is taking time for me to adjust to, I'd say it's 2x as heavy as the MX518.
Battery life is "ok" first charge I got about 6 days out of it, and that is with heavy usage, my friends who also are heavy gamers say they get about 2 weeks out of their mx1000.
It charges pretty fast, full charge in a couple of hours.
Gaming, i've having trouble binding the thumb buttons in games like BF2 and 2142 Beta, however that might be a setpoint issue that can be easily fixed, though i've been unable to fix it yet.
The rubber "sliders" on the bottom of this mouse are very very smooth, as opposed to the hard plastic "sliders" on the MX518, it makes managing the extra weight easier.
If some sort of software can be released to make all the buttons fully bindable, i'd say this mouse is the best on the market, the thumb slider is kinda just for show, but in a game where reflexes are less important, like say an RTS game, it might come in handy, it's not really a button you can get to in a hurry, maybe with some practice you could.