I'm glad to see the questions start flying. Basically, it works like this:
You run a program on your Blackberry. You can force it to sync, or set it to auto-sync. All updates are reflected on our webmail immediately. I, for one, set it to auto sync.
To sync with Outlook, you simply install a program on Outlook. Same as above, force or auto sync is possible.
The program is sourced from Funambol Mobile 2.0 Messaging Powered by Open Source
We configure it to work on our servers and do the purchase of the software up front. That way, we use a time-tested application that has been wildly successful and implement it with our servers.
I hope this helps!