Without checking each commit, I'm pretty sure you're missing some important changes such as IPV6 support (crucial, IMO!) and password hashing changes that break any possible downgrade from 1.8 to 1.7.4. There are also some other minor changes such as compacting numbers (e.g.: "1.5k views"), being able to specify decimal separators, switching to schema.org microdata or increasing post character limit. I'm sure I'm missing many more here.
Apart from what has been done, there is a sort of release backlog which Scott mentioned some time ago: http://www.question2answer.org/qa/45239/show=45265#a45265
. That's the closest thing to an ETA. In my personal opinion, there is still a long way to go but it is a matter of moving one step at a time.