I've been having a lot of fun beta reading. It's always satisfying when the other writer is, you know, good-- excellent is even better-- because then you feel like you're privy to something, and that you're helping with something important. And of course, getting your stuff read in return is awesome. I suppose it's a little nerve wracking when you know the other writer is a good writer, and you hope they think the same of you. But the important thing is to improve, and getting your stuff read and commented on is essential, as long as you find beta readers with some sense.
It's also a great way to connect with other writers, because they need and want it as badly as you. I had been a little afraid that other writers, especially strangers, might react poorly to my critiques, but so far that hasn't happened.
Also? Bonus if the other writer(s) are old friends from High School.