I got my "Thanks for signing up!" email via Launchrock on 14 Sept 2011, and haven't got a single email from you since... (email address as per my HN profile, if you want to look it up)
Same date for me. It's really a pity that nothing has been released for so long. Restricting open signups is fine, but the fact that people request invites means that there is definite support for the product, and those people are clearly willing to put up with a few bugs. These are exactly the kind of people who add fantastic value to the product, since you're essentially getting free product testing from people who are already passionate about the product.
Same story here. Exactly the same date (14 September 2011), haven't heard anything since.