Where do you find yourself with respect to the rumors of a new iPod touch somewhere in the pipeline? Having a slew of case manufacturers showing products with cutouts for a camera strikes me as enticing but ultimately unconvincing; hearing from Pinch Media, however, raises the credibility level to 'high.' The App Store analytics provider has confirmed that instances of an "iPod 3,1" model have begun showing up in the usage logs from apps that have implemented Pinch's tracking tools.
What could this possibly mean? Well, going back to March of this year, the BGR team sussed out a few future model IDs from a beta of the iPhone 3.0 firmware, including the iPod 3,1 listing; Pinch says that the device type first started showing up in April, and sightings picked up in May. Pinch's stats should be taken quite seriously, as the company first announced appearances of the model indicator that eventually revealed itself as the iPhone 3GS way back in January.
If that timeline were to hold true again, we wouldn't expect to see the iPod touch next-gen on store shelves before the holiday shopping season... but it's likely that the engineering effort for the new touch will bootstrap off of the iPhone 3GS platform, and the QA/testing cycle for the device will probably be quite a bit shorter than it would be for a new phone. If I had to guess... perhaps a Steve-enabled press event during the last week of July? Should be lively.
[As noted in the comments, Apple's track record for iPod introductions does have a consistent tick-tock rhythm to it: betting on a September launch for the new touch would be a prudent call.]