Erich Schubert asserts that X.Org is not ready for Sarge. Firstly, it was never proposed for Sarge (monolithic or modular), so that's kind of a moot point.

Secondly, he points to a bug opened today on Radeon, and declares that it is undoubtedly only one of a massive number of problems waiting under the surface. This bug only affected one very specific class of chips (rv100/rv200, aka Radeon 7000/7200; not r100 or r200, which are the same class), it was opened today with a patch from Dave Airlie, and as I read that blog entry, I had a test X.Org build running around my machine with that patch already included, as I'd seen the leadup to that bug on IRC, and had an X.Org upload planned anyway. So, I doubt a problem that only affected an infinitesmal percentage of users (Radeon 7500s are far more popular than 7000s in that class, and I'm not entirely convinced anyone actually owns a 7200), that was resolved as soon as it conclusively came up, can be a pointer to anything.

In fact, I think you will find the amount of hardware support in X.Org (out of the largest three vendors, all have new chipsets supported in X.Org that aren't supported in XFree86 4.3 -- ATI's r4xx series[0], nVidia's GeForce6 series of chips[1], and Intel's i9xx series[2], are totally unsupported) is so vastly improved that, even if the 'everything is broken and no-one noticed until now' allegation is true, the staggering weight of hardware supported under X.Org but not under XFree86 would be enough to counter this. Also, with Ubuntu, Fedora Core, Mandrake, SuSE, FreeBSD, Gentoo, and everyone else on the planet using X.Org at this stage, I think if it had massive problems, then it would be *very* well-documented.

I don't think extrapolating from one specific (and very quickly-fixed) problem to all of X.Org being totally unusable is valid, or fair.

PS: Ubuntu.
PPS: r100 is Radeon 7500, rv100 is Radeon 7000, and rv200 is Radeon 7200; neither of the latter two are very widely-used at all.

[0]: Not to mention massively improved display detection for every other chipset.
[1]: I believe Debian's XFree86 packages have some of this support backported, but not all.
[2]: And for i8xx chipsets also, widescreen/non-standard displays are detected and set up just fine without needing to use 855patch, 865resolution, or any of that class of monumental hacks.