Some more uses / benefits:
It's also a really good way to stay in touch with alumni from your law school class, undergrad, and even high school as you all move through your professional careers.
For example, check out LinkedIn Classmates:
http://blog.linkedin.com/2011/10/19/lin ... lassmates/.
Some people use LinkedIn like Twitter/Facebook, and post updates to their status. You can do that but be careful you don't come off as stupid.
Also, you can follow law firms you are interested in. Just recently LinkedIn allowed pages to make updates, so you will be able to see whatever updates firms are interested in pushing out.
It's interesting to look at a firm's stats on LinkedIn and check out where people go after; where they were before. This is a nice way to see lateral and exit options.
You can join career-related groups and follow discussions. There are some interesting legal recruiting groups with decent conversations about the legal market.
Definitely join the LinkedIn equivalent of groups you've participated in, such as extracurricular activities.
Try to get to 500+ connections. This is the highest that will show on your profile, and for better or worse, impresses recruiters and other people.
Easter egg: You can run ads on LinkedIn for your job search. For example, I ran ads before OCI targeting all Partners and HR employees from a certain firm. It only cost about $15 because there were only a few clicks, but it definitely got my profile viewed by partners of said firm.
Finally, put serious thought into the pro subscription, if you can afford it. The benefits are several--- you can see exactly who viewed your profile and most importantly you can create a custom linkedin.com/in/NAME URL. This has invaluable SEO (search engine optimization) benefits, and when people Google your name, your LinkedIn url will be high up in the results page (usually top 4). Also, you can use a custom URL in your email signature, and it looks sleek.
HTH.