Microsoft is inviting select Xbox Live subscribers to sign up between now and October 21 for what it calls an "exclusive pilot rewards program," promising unspecified "cool stuff" to those who register. The company sent email to a limited number of subscribers, some of whom forwarded their invitations on to consumer weblog Kotaku for its report. "So, you click the button below and register to let us know you want in and pretty soon we'll let you know if you got in or not - and not everyone will (that's why it's called exclusive)," instructed the emails. "This offer is for a select few - you can't send it to anyone else (why would you send something this awesome to someone else, are you nuts?). If you make the cut, you can pass or opt-out whenever you want. But then you'll never know how it ended." In controversial comments yesterday, Wedbush Morgan analyst Michael Pachter speculated that it would be a logical strategy for Microsoft to offer several subscription "tiers" for Xbox Live subscribers, with DLC discounts and other rewards as a sensible incentive for the top tier -- which he thinks could cost as much as $100. Microsoft, however, has declined to comment on any such tier, and has not explained any further details on its aims with the pilot rewards program.