Not to threadjack, but I had an icon up at the top of my stock D1 the other day I'd never seen before too. Looked like two little circular arrows pointing around each other in a clockwise direction. I don't see it in rawveeda's image. Possibly a "searching for / connecting to network" icon...?
Oddly, that's not anywhere in the manual (so we can all be spared a snarky RTFM response).
That's the synchronization notification, basically just telling you it is syncing with the server for e-mails, contacts, etc.
I normally only see that when I have had my phone off for a while and it's pulling down a lot of data.