The Opera 6.0 TP2 for linux is to buggy yet. The final for windows is excellent though. But I won't change my linux for anti-aliased fonts. Maybe when I get a copy of Visual Studio .Net

As for the security issues for windows, I guess nobody will choose windows over whatever os. But MS got lots of great developers on their salary-list so some good thing have to come out. The AA stuff is one of them.

What MS have found out, is that the reading on a computer screen is 20-30% slower than reading from a piece of paper. So that's what the AA stuff is for. More comfortable reading equals faster reading.