You are right. What I mean is 2nd revision of the 11.6".
And I agree. What I mean is changes to the specs offered. Could have been more clear on my part.
In any case, the question to me is whether the next generation is likely to be enough of a step up to justify upgrading from the current generation. If they just swap the Core 2 Duo/NVIDIA 320m combo for a straight Sandy Bridge Core i3, I'm guessing Rev D owners won't be tempted to upgrade and will wait for the 2012 update.
Although the CPU specs have barely moved since the Rev A, the Air has had a lot of other, more significant updates. In retrospect, Apple likely would have been better off using a low voltage Merom with the Rev A (say the 1.2GHz) rather than the 1.6GHz given all the overheating issues, and then switch to the 1.4GHz Penryn with the later versions. The heat issues got marginally better with the Rev B, but it wasn't until the Rev D that Apple really figured out how to vent it properly, thus getting the full benefit of the processor speed. At the same time, the integrated graphics improved about 8-fold, and the SSD improved 3 to 4-fold.
By comparison, the Rev E may be more like the Rev C in that it simply keeps pace rather than provides a significant update.