I know this is an older post but...
Not sure of the technical details of how Orb handles streams however, I have a Toshiba laptop ($500.00 @ Walmart) running Windows Vista Home premium and it streams to my N810 very well with no probs. Takes the files about 10-15 seconds to load and files usually play without skipping. My only lament is that you can only play files in one folder at a time.
Orb integrates well in both Canola and Media Box.
Over all I am very pleased with the performance of this free service.
My PC is decently powerful so there shouldn't be a bottle neck on that end.
Thanks!