A CRIME SSL/TLS attack is very dangerous. I'll answer your questions one by one.
1. SSL stands for Secure Shadow Listener. Basically(in words a script kiddie can understand) what this means is that your site is vulnerable to someone installing a very sneaky listener program on your site. Do you have any identifying information linking yourself to your site? I'm sure you do. It's very hard to avoid this and I doubt you used a elite proxy when you built your website. The SSL virus siphons off information about you from your site. The TLS part is where the exploiting happens. Your website could very easily get rooted and defaced.
2. Hmm. I'd say it would easily be a 3. These attacks are pretty easy to do. I myself find it tempting but since you asked respectably I think I'll leave it alone.
3. Absolutely.