I've been using Google Reader for my RSS feeds for a long time now. I think that it started because I needed an RSS reader and already had a Google account, so it was a natural fit.
I've been meaning to switch for a while now, ever since Google announced that it would be shuttering Reader because it couldn't figure out where to put the ads. Fortunately, I remembered that this morning, since tomorrow is the big day. I've already copied everything (not just Reader subscriptions) via Google Takeout - it's a good backup to have, anyway - and I've gone ahead and switched to The Old Reader, since it was based on Google Reader ages ago and, well, my main preference would be to just keep Google Reader, so I want something as close to it as possible.
There are lots of other RSS readers out there, of course. Have you remembered to switch?
(Also, if you feel like commenting, let me know which RSS reader you use and why.)