I made the decision to only buy PDFs for 4e about a year ago, so to be technical, it's less that I'm boycotting WotC then it is that WotC is boycotting me.
Here's what gets me about WotC's decision:
We can divide current 4e PDF purchasers into two camps, those who would never download a PDF illegally and those who would, but who prefer to pay for the PDF when that option is afforded to them.
With WotC's decision, the first group stops giving WotC money and the second group stops giving them money AND starts downloading illegally.
So somehow, in an effort to fight piracy, WotC has settled on the one course of action that is 100% guaranteed to INCREASE piracy.
The D&D rulebooks were available before there were legally available PDFs (heck, the PDFs of the core books came out before the core books), and illegal PDFs will still be available moving forward.
At best, they'll slow the dissemination of new books, but if that was their goal, there'd be no point in pulling down the PDFs of any book that was already available for illegal download. Unless you're going to magically remove all of those old PDFs from the torrent sites, there's no point in shutting down the sale of those same PDFs through legal channels. None. It's moronic.