A few observations from the Australian innings:
I'm a big fan of Vaughan's captaincy usually, but it was sub-par today imo. He let the pressure off on several occasions with bizarre bowling changes, none so shocking as bringing himself on with Australia on the ropes to let in a 13 run over. He was also, as SP pointed out, a bit too negative at times.
England showed the value of 5 specialist bowlers today, I think. Even when Gough was getting pounded, there was still 40 overs from other specialists to come, which saved them from a huge total.
Harmison and especially Flintoff were fantastic today. Flintoff's 6 over spell in the middle overs was up there with Lee/McGrath in the last match as the best bowling I've seen so far in the series. Harmison was dangerous throughout and is clearly going to be a menace in the tests if he gets a wicket with uneven bounce like this one.
Symonds and Hussey were just great, and I was really impressed with Ponting's touch as well before his dumb shot to get out. Lee's batting at the death saved Australia from falling to a poor total, as well.
Martyn was clearly not out, imo. Pietersen had that ball in his fingers, but the ground pushed it into his hand and gave him control over it. I wasn't particularly impressed to see him claim it.
Australia got 20 less than they should have, but 260 odd is still a tricky total on this wicket, which is only going to get slower and more uneven, and with the clouds coming in and the lights coming on, Lee and McGrath will get it to do a bit.
Aside from that, the thing which really struck me was the high standard of play. England for the most part bowled very well, Australia batted very well, the fielding was good, and it was good to watch.
Like last game, if either Flintoff or Pietersen play well, England will win, otherwise Australia should take it on a wicket like this. It's not an easy chase at all. At a pinch, Australia by 19 runs.