Lordillingworth,
It records AVCHD, which is a .mt2s file extension. The camera is capable of recording at 1920x1080, but Final Cut Express only outputs at 1440x1080, so I do all my recording on the Canon at 1440x1080, that way, you just plug the Memory card into the Mac, the Mac sees its a Canon shared drive. Start up FCE... and use Log and Transfer. It will give you all the clips you've taped, and you can edit them right there before transfer. So, if you have a 4 minute clip of your dog and only want about 2 minutes of it, you can only have that section transfer over. Makes it really easy. I just grab all the clips, label them, and FCE transfers them over in real time.
iMovie 08 works as well, it will see the memory card as a camera and you can import "Large" to iMovie as well. I also brought these files into Power Directory 7 on the PC. That was simple too... just a quick import, no re-encoding at all.
That movie I sampled here, was about 500 meg from FCE Quicktime... I used Visual Hub to create a MP4 of it and it was about 102 meg. Files sizes can be pretty large, no doubt about that. But it's just gorgeous to see the source material. You can also take the SDHC memory card and just stick it into a Playstation 3 and it will play them back, full 1080, right away. It's really nice.
Tom