It seems to me that the most practical mode for a small AVCHD cam is 30p. 24p looks juddery on Youtube and Vimeo, 60i doesn't look sharp when deinterlaced, and working with 60p is a little beyond the capabilities of Vegas and other video editing software. That leaves 30p as the most practical choice (at least in the United States).
What are the best 30p options in a small camcorders. The Panasonic TM-700 series doesn't do 30p, the Canon SX-1 does a non-standard frame-rate of exactly 30p rather the industry standard 29.97. This is fine if you are using Neo Scene since it corrects this but a pain otherwise.
What are the other 30p options are there?