I've never been climbing before, but I went to the Yelp Quirks Out event earlier this week and LOVED it - the instructors were super helpful and made learning how to use the ropes and belay your partner easy. I also really liked the social atmosphere - every climber I encountered was friendly and willing to give out tips.
There were lots of climbers, so occasionally we had to wait for one of the easier routes to open up, but in general the facility was spacious and had a ton of options. Now I just need to convince all my friends to come climbing with me!