I’ve been waiting on this for a while, and missed the announcement that it was available, happened to see that Paul Waters had tried it via the weekly digest I get from LinkedIn. It runs on Tour, Curve, and Bold (my current phone). Installed easily enough, and the UI looks a like like a browser. You can view your network, view updates from your network, accept invitations, view profiles, and more. I can see it allowing me to do more timely invitations to people I meet at events. Was hoping to see some magic that made it easier to do this via phone, but no luck on that, you still search by name or invite by email address.
Worth getting if you use LI a lot. Details on the download are here.