How similar is it to Photoshop? I'd like to use it for vectoring. I've been using photoshop for about 10 years so I have an understanding of most of the tools. I'm wondering how smooth the transition will be, and if there's any recommended resources for figuring out Illustrator?

best way to learn a program is to open it up and play with it

then do illy tutorials to learn to use tools in ways you didn't think of, or don't understand

The best way is to go from illy to PS, but no one really starts that way.... GLHF with shapes/layers/and pen tool

There is a lot that you can do with it. Hotkeys are very similar. It is based on geometry and creating designs such as logos or something that needs scaled up a lot. It's great for using with Motion Graphics as well.