http://thebitpulse.com/2014/08/32-of-steam-greenlight-games-get-greenlit-and-other-valve-stats/
Right now, looking at Steam Greenlight page it shows the following:

3114 Greenlit items
4845 Released items
There seems to be a bug concerning number of released items. If you click through it, it only displays 562 entries which seems a lot more reasonable. What I'm not sure about is, what is the total number of items that are in Greenlight but that haven't been Greenlit yet? It would seem that 1730 items seen in screenshot above could be it, but I'm not sure. The list does have entries all the way back from 2012 when the service started up until today. If this indeed is the total number of games in Greenlight that haven't been Greenlit, it seem that they are accepting at least double the number of games compared to what they did 6 months back. The article says acceptance was around 32% and with these numbers it is about 64% acceptance rate (3114 accepted, 1730 not).
I'm planning on listing a game on Greenlight in about 9-12 months. My fear is that by that time Steam becomes what mobile app market is now. Easy to get in, but very hard to distinguish yourself from the crowd because of market saturation. Are my fears unfounded? Did I get some of my data wrong? Is there better data available somewhere?