Just wanted to let you know that despite 0 replies at least one guy researched the crap out of this :P
But after like 2 hours I got nothing.
Sites like keepvid.com or savevid.com rely on java, which the phone won't handle (skyfire is no help).
I found one promising site that claimed it was specifically for phones but all of my searches came up dry, the site just doesn't work.
Found a
cab here but it doesn't work on the new youtube format. Found an EXE that was part of the coreplayer youtube plugin, but it's old and doesn't work with the new format either... under the 0.1 version of
this page.
The most promising route was
http://www.keep-tube.com ...with a youtube url and the source of the youtube page, it spits back links for ALL versions of the video (including 720p, etc). I took some tedious steps to get the source of a youtube video page by opening a new tab, googling 'view source site', clicking the first result, pasting in the page I wanted the source for, clicking the button, spending an agonizing long time dragging my stylus across the entire wall of text, copying it, going to the keepvid tab, pasting it, and clicking the button. This got me the clickable links for the youtube vids, but clicking them just spit back some error like "the server refused your request". No idea what that is.
If someone wants to keep working that angle, it might turn into usable (albeit time-consuming) method.