There is no mistake. I know it's 25p and 30p on the sensor in a interlaced AVCHD wrapper. My issues are as follows (and they are major issues):
30p is almost universally hated by cinema guys, it is not superior to 25p or 24p, it is not a cinematic standard and it does not have the same cinematic aesthetics. It looks worse - much worse. Canon brought out a firmware update for the 5D Mark II to add 25/24p and we went crazy for it. Sony must have been asleep whilst this was happening.
To remove the interlaced wrapper in order to edit the video in Final Cut Pro or similar NLE software, you need to do time-consuming and complex de-interlacing whilst transcoding the footage which is totally unnecessary and a ball ache. It adds more work, more time and more confusion to the process of editing footage on a PC or Mac. When the Panasonic GH1 hack removed the 60i wrapper and added native 24/25p AVCHD (the Bluray standard), we went crazy for it. Sony must have been asleep whilst this was happening.
The bit rate of the codecs in the A55 and A580 are too low. 17Mbit AVCHD is the same as the Panasonic GH1 before the hack. Now we have 44Mbit and it looks MUCH better. You only have to see sample footage on Vimeo to tell this is the case. The Canon EOS line has universally stuck to 40Mbit+ H264 (the same core codec as AVCHD) and it looks much cleaner, with very little compression artefacts. Yes I know a low bit rate codec saves memory card space, but at least let us choose between image quality and saving disk space!
Meanwhile the MP4 progressive mode is 12Mbit 1440x1080 (like the cheap Sony compacts!), and has visibly more noise.
I am extremely disappointed with the whole thing and I honestly do not think anyone will buy an A55 for video, not when there is competition like this:
Nikon D3100 - low price and native 24p full HD, improved image processing to remove moire and aliasing artefacts
Panasonic GH1 - full manual control, decent AVCHD and with the hack, image quality and effortless editing of footage is present, plus the camera comes in at a very low price considering 2nd hand cost of kit lens which has full-time AF in video mode.
Canon 550D - full manual control, great codec, 24p, list goes on… and cheap too
Canon 5D Mark II - only one of it's kind, full frame and full HD. Used in Hollywood circles.
Runs rings around the Sony DSLRs and has full manual controls, 24p.
Canon 7D - as 550D but weather sealed and slightly better high ISO.
Who'd buy a A55 for video now?