I cruised on Getaway in a solo cabin last month. It was not bad at all and I met a couple of cool people. It wouldn't be my cruise preference, but I tagged on with friends pretty late in the game when all were paired up already and didn't feel like paying 200% for a veranda or suite and I didn't want to be the 3rd in an already small cabin either!

Don't rule out meeting suitable cruise companions around these parts either. I've cruised with a friend from FT (we've known each other 12+ years now but met at a Do) and a friend from another travel group.