I'm not sure if people are aware of this or not but thought I'd mention it anyway.
I'm successfully editing AVCHD files from my Canon HF100 in Windows Movie Maker (Vista Premium). All you need to do is install the Pixela ImageMixer software. This installs a Directshow Video decoder for the native AVCHD files off the camcorder. I'm not sure if this works with other camcorders but worth a try (I would install the software that comes with your camcorder before trying WMM).
With the correct Directshow filters installed it's a simple case of dragging and dropping the clips from Explorer into WMM. On my PC (Quad Core 6600, 4GB RAM) it's pretty quick to edit these files and although WMM doesn't have any fancy capabilities I still prefer to use it over Premiere Elements 7 for a lot of things. (And I still use Pixela ImageMixer for very basic edits and other stuff).
What helps is to add thumbnailing for the AVCHD files in Explorer:
Add these lines to a text file, save with a .reg extension and double click to update registry:
Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\.mts\ShellEx\{BB2E617C-0920-11D1-9A0B-00C04FC2D6C1}]@="{c5a40261-cd64-4ccf-84cb-c394da41d590}"
[HKEY_CLASSES_ROOT\.m2t\ShellEx\{BB2E617C-0920-11D1-9A0B-00C04FC2D6C1}]@="{c5a40261-cd64-4ccf-84cb-c394da41d590}"
[HKEY_CLASSES_ROOT\.m2ts\ShellEx\{BB2E617C-0920-11D1-9A0B-00C04FC2D6C1}]@="{c5a40261-cd64-4ccf-84cb-c394da41d590}"
Or click
here to download a file I've already done for you!
You may need a reboot to get the thumbnails to display. I also needed to delete my thumbnail cache to force it to start thumbnailing - in Vista run disk cleanup (type "cleanup" from start). Select "thumbnails" and delete.
For uploading to the web HD videos I export using the 720p profile and upload to Vimeo with excellent results.
Hope this is of use to someone.
Cheer
Gidon