I don't know if anyone's ever used this on a PC but a few years back I found it indispensible for updating contacts. Since I moved to the Mac I've had to manually update my Plaxo contacts. This beta version works great and is welcome news for OS X: http://www.plaxo.com/downloads/mac
At least once a week, I get an email requesting me to update my contact info to some online database established by contacts. I went thru the process a couple of times, but I generally ignore most requests. With this toolbar, I may just change my mind and join the bandwagon!
found out about this news too. before, plaxo took so long to make a mac version of this great PIM sync software, i had to settle for .mac. now, it seems like i can sync data for free
I just got around to syncing my phone's phonebook to my Mac (borrowed a USB Bluetooth dongle). Then I noticed the Plaxo notifications on my Windoze work PC (which I generally ignore - just let the whole thing run invisibly in the background). Figured, "Hey, might as well see if I can use Plaxo to sync all my contacts on all devices/platforms." Lo and behold, Plaxo has a Mac toolbar - and it ain't beta anymore. Neat.