Using Xobni

So, what's Xobni? There are some good reviews here by ReadWriteWeb, Web Worker Daily and TechCrunch (there's a summarizing video there too).
Some problems I am experiencing are: Outlook seems to slow down somewhat and it seems to dig up old tasks that I finished a long time ago and present them as To Do's. And my SyncMyCal has disappeared...
I was wondering if Xobni also searches my archived items. That would be nice and it would also explain why it shows my old To Do's.