I quite enjoy Rift, and am looking forward to playing it more, going further. I know that an MMO needs people playing it, and that Trion is privately held. That makes getting subscription numbers a bit difficult to get.
However, I figure that unique visitors to the Trion website might be a useful proxy to understand the interest level that the internet has in Rift. Using Google Trends, and using eve-online.com as a comparison (due to similar scale, discovered thanks to experimentation), here's the picture:
Here's the full data.
I'm not super-excited about this, and I really hope that Storm Legion reverses this trend. I would also call on all of y'all who are passionate about Rift to continue talking it up to people who aren't playing.