Bangladesh have played remarkably well. People will talk about Australia's failings, and rightly so, but the whole time I was watching the two Bangladesh spinners bowling earlier, I was comparing it to the treatment Australia got on the two subcontinent tours in 2004. Genuinely, it was comparable. Bangladesh batted well and used the conditions and the lacklustre Australian efforts (which were only bad for one session, really) perfectly, and then they really piled on the pressure. Bashar attacked constantly without leaking runs, and the quality bowling pushed Australia's batsman right on to the back foot.
Australia for their own part looked absolutely shellshocked. Aside from Clarke and Gilchrist, nobody gave appropriate respect to the bowling and the circumstances. They were either too defensive or too aggressive. Gilchrist played a fantastic innings under the circumstances, and kept hopes alive for a competitive score of 250+
I think that the first three Australian wickets were fairly unlucky, particularly Ponting and Martyn who got done in by unpredictable bounce, but the key issue was that after they got a few early wickets, Bangladesh had the talent and the killer instinct to really follow it up with some excellent bowling and keep Australia under pressure. There's no doubt who the more talented side is, and the game is still wide open if Australia can get within 150 or so and then bowl very well, but Bangladesh have to be favourites to win at this point, and that alone is an amazing statement.
The last three times Australia has gone to the subcontinent to play the three major teams of the region, the scoreline has been 3-0, 3-0 and 2-1. That's 1 loss in 11 tests (1 draw). Bangladesh might match that on their first try.