I think I joined it once long ago, then unsubed. I do recall just a few weeks ago trying to sign up as someone was asking me to join LinkedIn. I stopped half way through the annoying too-many-questions too-much-personal information signup requirements and left, unsubscribed, in disgust.

Last year it made a whole $16 million. Wheeee.

Now it miraculously has a market value of $8.7 billion.

Barron's nicely highlights the insanity of that market evaluation: LinkedIn in has "550 times 2010 profit of 17 cents a share. Google (GOOG) is valued at five times revenue and 20 times trailing earnings."

550 times revenue -- that is one heck of a gamble.

Barron's suggests caution: "LinkedIn appears to have a sustainable business model geared toward selling access to its member data to potential employers and advertisers, but its valuation looks steep, at more than 20 times possible 2011 revenues of $400 million . .

most highfliers flame out, and the odds are long that LinkedIn can justify its huge market value. Investors probably should stay away."

I agree.

I'm LinkedOut.