Upgrading your laptop's hardware is not that easy. Of course, if you have some experience with it, it will probably be little to no hassle.
If you decide it's worth all the effort you put into it (replacing hardware, with risk of not getting it right), you should definately do it! But I would wait a little bit with it, as not a lot of devices support USB 3.0 already..
PS: sorry for bad language, I'm really in a hurry :)