Evolution Data Server (or E-D-S) stores information on contacts, calendar events and to do lists inside Gnome, however there aren’t many (any) ways of putting data into E-D-S, except through Evolution itself. Evolution which is primarily a Microsoft Outlook clone, is basically an email program, that is nasty. The contacts/calendar functionality which i’ll use irregularly, isn’t worth swapping my almost perfect email client which I use all the time, and I refuse to use both.
The other problem with e-d-s and contacts is that of data sharing, syncronising to my iPaq is more effort than it’s worth and there is no way for thunderbird to access my contacts stored away in evolution data server.
This makes it hard to benefit from some of the tasty integration work that’s been put into Gnome.
However with more attention being focused onMultisync and similar projects, hopefully there’ll soon be a break through where everything works nice together.