Sub-pixel Anti Aliasing in Mustang
Ever since Microsoft added support for sub pixel anti aliasing in Windows (a well known technology they decided to label ClearType) many people wanted to get it in Swing. Sure we had access to anti-aliased text (and in J2SE 5.0 we could even use the tricky -Dswing.aatext=true to activate it globally) but it was far from good for small font sizes.
Thankfully, Sun's guys did a great job here and recently closed RFE #4726365 Java 2D to support LCD optimized anti-aliased text (sub-pixel resolution). LCD optimized text is even turned on or off according to the host settings.
We can expect a lot of problems at first (like custom components or UI using API not supporting the new AA algorithm) but eventually we'll have nice looking text in our Swing apps.
Mustang is definitely exciting for rich clients developers \o/