We wondered what the benefits were of upgrading from a basic to a premium LinkedIn account and these are the responses we had:
It does not give you, as far as I know, "better communication". You have the same tools, like Introductions, but more of them. You get a certain number of free Inmails, which I guess you could call "enhanced access to decision makers", but I think that's an overstatement. And you can receive Free Inmails. The search tools are exactly the same although you get to see complete profiles of people who are not in your network. If you need more of the same, by all means upgrade. But don't expect a huge difference.
Premium accounts give you more ways to reach or be reached by the right people on LinkedIn – including better communication, more powerful search tools, and enhanced access to decision makers and other resources on LinkedIn. Take a look at http://www.linkedin.com/static?key=business_info_more&trk=hb_ft_upyracct .
Free Inmails unlimited. - Introductions. - Better Business prospects
Anyone else have more to add?