I don't really get what's so great about Xobni.
I use it at work, but except for the contact search and attachment features it isn't very useful.<p>It's just as good as many addons developped without many resources for Thunderbird, not worth a 10M funding in my opinion.
xobni is awesome. I used it when I worked at a Fortune 500 company and kept recommending it to people. I pretty much only used the attachment and contact features though. Good luck to them!