The trouble is, the current standardisation processes are far too slow to be practically useful, while the breakneck pace of experimental feature development is too fast to keep up, so there is no useful definition of "a little" in your suggestion that we can use for planning new web projects and making decisions about which technologies we will rely on.
> There are philosophically and commercially opposed interests involved there.
It also doesn't help that both sides throw out FUD as if it's going out of fashion, and that some of the (acknowledged) patent encumbered formats are technically far superior to the (possibly) unencumbered ones. That means until either the software patent madness is fixed or organisations like Mozilla start putting up hard cash, their integrated video functionality will never be as good as what you can get in something like IE (or, apparently, Chrome, since Google seem to have quietly dropped their policy of discontinuing support for H.264).
> Could you cite or give examples of these [font bugs in Firefox]?
On Windows systems, the kerning is very odd in a lot of fonts since they moved to the new rendering engine a while back. The spacing following a capital T is usually way too tight, and in some fonts there are a few other examples as well. This can render pages completely illegible at typical body text sizes.
Also, take a Windows 7 computer with a few Adobe professional OpenType fonts installed locally -- probably some that come with Creative Suite would do -- and just try selecting those fonts using CSS in recent versions of Firefox. It simply doesn't work and falls back to the next font family in the list, though the same page will find the fonts and render quite happily in other browsers on Windows 7, or in the same version of Firefox on Windows XP for that matter.
Most currently available web fonts also seem to look terrible (poorly hinted, terrible aliasing) on Windows XP in Firefox, but since they don't look great in other browsers either and they look better in Firefox on Windows 7, I'm inclined to point the finger more at Windows XP than Firefox in that case.