When you go to Oscar's make sure you get a table in the dome area. It has a nice atmosphere, with a really great view of Fremont Street.
I started off in the bar area, which has a happy hour every day, including weekends. It is a really cool area and the bartenders are great, along with the drinks.
For dinner I had the salmon and the filet, which did not disappoint. Oddly enough, one of the standouts of the dinner was the dessert, though. We got a layered chocolate mousse, that was the best I have ever had.
It's not cheap, but if you are looking for a really nice dinner in downtown Vegas, Oscar's won't disappoint.