I've spent many months, desperate to figure out what the thrill is with Second Life. For quite a long while it would not work on my old iBook. However, it runs beautifully on my shiny new MacBook. After reading a friend's NaNoWriMo Novel part of which is set in SL I was itching to get back in world.
Ok, I still don't get quite get it. I love being able to change appearance on a whim. I love all the crazy things that are possible. Flying! I've even had a reference interaction on Info Island. There's all kinds of potential for learning. (Right now there's a display of different winter holidays on Info Island.) There are book discussions and concerts and even religious services in world. There is no end to possibility in SL. So, this is the awesome.
However, it makes me dizzy. I have to be carefully about my movements or I develop a splitting headache. Also, I'm not comfortable chatting with random avatars. I experience overload, trying to navigate myself, chat with people and figure out gestures I'm supposed to make. I can't do all these things at once. Furthermore, so much of SL requires actual money. You can buy clothes and land, but you can also buy eyeballs, hairstyles and skin.
I'll be the first to admit that I'm not experienced with SL to really comment on it. I just don't know how to leap that hurdle of being a neophyte, nor if I even want to.