Plaxo is missing one feature that I think would elevate it to killer app. Interestingly, you hit on this feature in a post some time in the past year. I coded a proof of concept a few weeks ago, and showed it to about 20 associates in the industry, and all said that it was a viable answer. Alas... There Is No More VC In This Country. Period. And I'm not going to quit my day job.