SOPA/Protect IP blackouts

Wikipedia has just announced it will be doing a 24 hour (5am to 5am GMT) blackout of their site on Wednesday. They join other sites like Reddit, Boing Boing, XDA Developers. Personally, I'm doing the same for my site.

Do you think these blackouts will work or will people just ignore them? Also, do you think sites like The Verge, Engadget, CNET, Gizmodo, etc. should follow suit?