John Paczkowski at All Things D writes this morning that network operators seem to be showing strong interest in BlackBerry 10, Research In Motion’s new operating system set to come to market early next year. Jefferies & Co. analyst Peter Misek raised his rating on RIM shares and doubled his price target to $10 on Tuesday, Paczkowski notes, after hearing surprisingly positive feedback from carriers.

“We are a bit puzzled as we expected a more muted response given BB10 is two years late and RIM’s market share has plunged from 20 percent to 5 percent,” Misek wrote.

While BlackBerry 10 is still a long shot, it’s hard to overstate how important carriers will have to be in any RIM comeback. Network operators not only have huge distribution footprints, they have the marketing muscle to make or break a handset or platform. RIM knows this very well from its experience with the BlackBerry Curve, which Verizon Wireless helped to become the top-selling handset in early 2009.

Carriers have long wanted to see the emergence of a third platform that could compete with Android and iOS. The window has been open for Windows Phone to break out of the pack of also-rans, but Microsoft’s operating system continues to struggle. A big carrier push at launch would go a very long way toward getting RIM back into the smartphone game — and that would be very bag news for Microsoft’s mobile ambitions.