I agree with Alistair...very useful for business professionals. I use it to investigate companies and find contacts among them. In one recent case I was having a lot of issues with a supplier engaging with us. I used LinkedIn to find the UK CEO, sent him an InMail and bingo the next day they are all over us helping....
It is also useful for tagging contacts...but like an electronic business card library...
Job seeking I have used in the past...but here I have a word of caution. I as recently "added" by a number of recruiters...they're looking to offer me jobs I thought...not at all. In fact they were harvesting my contacts for people who matched what they needed. SO now I have blocked all but a few recruiters who have helped me in the past....
I must admit though, if your're retired I simply would not see the point of joining it all......
