Not quite dead but almost in my opinion. The problem is the ROI. For example I used to get about 10-15% ROI on SNGS on the Cake / Revolution Network. Now it seems like I'm playing to get 2.5%-5% ROI. At the $5 SNG Level that I like to play, you are going to have 3 to 5 good players in each game. Thus, your ROI goes way down, and so does your hourly rate.
So it gets to the point where McDonalds is a better way to make money per hour. You think, well, I'll just play a greater volume. Well, there isn't that much volume even at $5! If you want to play $10 and $15 SNGS on Revolution, you'll get 1/2 to 1/3 of the volume.
Then of course you deal with long cashout times, high cashout fees, and even the possibility of bounced checks, making your effective cashout time even higher.
Pitfalls all the way.