I’m not, but it’s mainly because there’s usually no interesting candidates. Also, I have found that in my state we do a caucus, which is totally different from a primary. (And I’ve heard is a lot more fun.) Plus, it seems republicans will be testing a new online version of it this year. I’m not sure which side I go for at this point either. On top of that, work could stop me from voting in the first place.
So yeah, even if I was registered, I’ve got problems that prevent me from doing so. I just hope we don’t get screwed over this election. (I consider the last time we got screwed over was in 2004, when George W. Bush got a Second Term. I’ve been okay with Obama getting 2 terms.)