Jesus this thread, look at the statistics 9% of Wharton students go into PE/VC after graduation. While not HBS high, it is still a significant figure. So you will have a good shot. Most current students told me that provided you have some PE experience you will definitely get an interview and the rest is left to you, however, if you do not have pre-MBA PE experience you're screwed.
As for recruiting, Most PE firms recruit at Wharton and follow what's called enterprise recruiting, i.e. less structured. That is not to say there is not a lot of job posts, there are, it just means that they don't have a highly detailed process like the consulting and IBanking firms who are the only ones that really follow that structured process. Similar to undergrad, this is done to scoop up candidates that are feeling overwhelmed by the $$$, and would like some certainty to the process.