I'm not sure if this relates to my system or a particular (undocumented) tweak in the latest build, but all the outstanding text peculiarities have cleared up.
For example, in ProFont 9pt anti-aliased I was seeing a lowercase 'L' being represented at double thickness (2px). This has all gone, and it's *beautiful*.
Along with all the other visual tweaks in the latest build, TextMate is really sweeping me away.
My dollars are going down today. New customer.
drew.