The reason I don't use G+ is that I can get it's functionality elsewhere. I follow tech people on twitter, and few big names on facebook (Robert Scoble, Zuck etc). If more people used it, I'd be tempted to use G+. I personally don't think twitter's character limit is archaic, and it's what makes the platform what it is.
Yeah I know what you mean re:twitter. I go back and forth between what I think about twitter. The simplicity of it is a godsend in comparison with other social media. On the other hand, as @strangegibbersh@ posted above, the reverse order of longer posts and conversations makes it hard to piece together what someone is saying and makes the platform seem a little messy to me (also, with all that tweeting lingo, it sometimes takes me forever just to figure out what someone is saying). With G+, I like it because it does a lot of things pretty well and has a pretty clean interface. Unfortunately, being a jack-of-all-trades means it is a master of none. sigh I'm glad there's competition, but boy would it be nice if there were one simple platform that all my friends and everybody I want to follow were on.