Holy Shit! What an unexpected turn of events. We thought Aizen was done for, then BAM! He transforms.

Then we thought Ichigo was screwed after Aizen transformed and womped on him. Things were looking bleak for Ichigo. But AMAZINGLY (who would have predicted?) Ichigo is unharmed and is ready to unleash, get this, the FINAL Getsuga Tenshou!

I don't see Aizen being able to get out of this jam. His heart would have to REALLY desire it and he'd have to butter up to the Hougyoku.