Two things that are worth noting is that MPX just works with applications today. While they're unable to take full advantage of it, even if you have multiple cursors, you'll be able to interact with multiple legacy apps at the same time. Getting this to work fine was most of the reason why MPX took so long to arrive: having this kind of thing work correctly with, say, Firefox, is next to impossible.
Also, 1.10 will be part of 7.8. Externally-built drivers will still be supported, and the plan is -- when we're ready, which may or may not be 1.10 -- to start merging in the more active drivers, such as Intel and Radeon. That these drivers also have KMS support is not coincidental; hopefully having the actual driver code in a separate project means that the drivers themselves will settle down, and thus make them vastly more suitable for merging into the main server tree.
The fear of merging them originally was that with an unstable master and an ever-changing driver base, the odds of getting the core server and the drivers working at the same time were indistinguishable from zero. Hopefully the combination of the new development process and KMS can allay these fears.