» Joyent, in contrast, is Groupware 2.0 for small teams. Zimbra's 100,000 user deployment pitch is very different than Joyent's pitch as a hosted service with an offering that maxes out at 25 people. Want 50 people? Buy two 25-packs for now. (Note: they're working on alternate approaches to this limit, or you can buy and host your own "Accelerator" appliance). Question the approach, but I admire a company that knows its target customer and sticks to it.

» Zimbra is open source and wants to be the Linux of Groupware, They started off boasting of their 100,000 seat deployment to H&R Block, and after the demo I can see why they're getting that kind of traction so soon after launch 6 months ago. The app (web client + server) is incredibly fast, ajaxy-interactive, and in general a well thought out integration of shared email, calendars, and little apps called Zimlets.