So, PAX East tickets are on sale -- http://www.paxsite.com/
3 day and Saturday are sold out (but if you want to pay triple the price, check boston.craigslist.org). I've opted to purchase Sunday tickets.
I used to go to PAX prime every year. Now the tickets are usually sold out before I even get the notice that they are on sale.
Of course it wouldn't be quite as fun without the CoH stuff there anyway.