I stayed here for RollerCon 2011 and had a decent experience, but a couple big problems. Checkin was an absolute nightmare; it took over an hour for a line that wasn't really that long. Upon arrival, I discovered that I had accidentally booked a smoking room through Orbitz (even though I specified that I wanted a non-smoking room, I somehow chose an "upgraded" room in a tower that ONLY has smoking rooms...wtf). The girl who checked me in said that she could get me a non-smoking room in another tower, but that it would cost extra. I agreed only because I didn't want to spend a week in a room that reeked of cigarettes.
Turns out, my new room came equipped with pillowtop mattresses and a mini fridge. I later wondered if I could have transferred to a room in another tower that didn't have all these bells and whistles and not have had to pay extra. Oh well...
The pool is a LOT smaller than the other Vegas hotels I have been to. The Riv is also not very convenient to other places on the strip. It IS, however, located very close to a Walgreen's where you can stock up on goodies for your mini fridge. The layout of the hotel is awful and it's hard to find anything -- but I suspect most Vegas hotels are arranged like this so that you find yourself getting lost in the massive casino.
At one point, the girl who I was sharing the hotel room with called down to the front desk to ask about using the safe that came in our room. She was on hold for 20 minutes and was transferred twice just to ask this simple question.
The accommodations are fine, but they will upcharge you for everything and the customer service blows. I would recommend finding lodging elsewhere on the strip.