While just a rumor at this point, Apple has yet to launch any testing of 10.7.1 and is heavily invested in 10.7.2 with beta 7 having come out recently. Apple may be preparing to beat their advertised iCloud launch estimate of this fall, though, September 21st is not that far off. Testing seeds take a few weeks to hammer out, and if Apple were to launch iCloud publicly Sept 21st then it makes sense that they have skipped 10.7.1.
Apple may also be facing pressure from Amazon and Google who are trying to bolster their cloud offerings after Apple’s announcements stole the show a few months back, and also they may be trying to beat the downturn in the economy and get as many users signed up as fast as possible. There’s also the guess that the iPhone 5 will be released in September as well which would coincide with 10.7.2 launching along with updated versions of iTunes and other associated apps and/or apps that currently have the triggered functionality inside them already.