I was recently considering to buy an A77.
After reading lots of reviews (actually, all), I realized that reviews are not sufficient: to be fair, a reviewer must take in account factors that I will happily ignore, say the quality of the jpeg engine or video recording. So there's a good chance that asking people and summing a sufficiently large number of opinions, you will be able to find more.
Second, since I already own several Alphas, I won't base my decision on "what this camera allows me to do". As a rule, all my cameras allow me to do what I want: probably because I select in advance the most suitable camera for a given task, so it's more likely to succeed.
I will base my decision on "what this camera allows me to do significantly better (or even that I can't do now)" minus "what big issues this is going to cause". Now, even if I personally like the A77 a lot, it has two problems: one, let's call it absolute and one relative.
The absolute issue is: for every "plus" feature, there's a downside in the camera itself. The sensor is 24MP but more noisy; the fixed mirror gives better AF but ISO 1600 is actually more like ISO 1000, etc.
Now, all this in practice is irrelevant. I'd bet, none of these issues is a real problem that will make my photos awful. I have wonderful pictures taken in low light with an A100, and no doubt the A77 is technically superior in every aspect.
The relative issue could be explained as follows.
Ideally a range of products is well-ordered, say the A580 > A550 > A500 > A450 and so on; to be the best, you just need to do better than current top (let's assume it's the A580, for the moment, given that the A700 is no more). Now, Sony in particular exhibits a strong non-linear behavior in history, they release models with random features in random order, so it's very difficult to compare cameras: is the A580 better than the A700? Hard to say! the A580 is younger, so it benefits from a newer technology.
Would you prefer a 20-year old Lamborghini or a modern BMW? Hard to say! I'd personally keep them both. But the A77 was supposed to be the modern Lamborghini so it should be better than everything else. Is it better than the A700 and the A580 simultaneously? Possibly, but not significantly.
If my BMW allows me to go from A to B in 1 hour, will I buy a Lamborghini that allows me to do the same in 55 minutes? Probably not.
Not buying is an option.