From a fellow Pro-Y NFO, it took about 5 1/2 months to get a prospective date, and then it moved a month further away. I still don't have my Final Select and it's going on 7 months. Part of my issue was that I was waiting for a rolled Intel board until Feb/March. Once I was Pro-N from that I "officially" started my wait, since Intel was my #1 choice when I applied.
I was originally told I would be in the September class, with several other December board applicants, but have since been changed to October. I don't expect you to wait as long though because there was an issue with over scheduling classes this summer.
Try not to get too antsy waiting for the letter (easier said than done I know)! It was a tough wait when I thought it was constantly around the corner. Just make sure you spend your time getting physically and mentally prepared and it will come soon enough. I got a summer gig to help pass the time. You can get much better gouge for when you'll be leaving from threads like NOPO's and here than your OR, in my experience. Cheers to waiting