Everything is done. I have a fully working KDE desktop, and the whole
system was compiled with GCC 4.3.0, CFLAGS="-O2 -march=core2
-fomit-frame-pointer -pipe" and LDFLAGS="-Wl,-O1 -Wl,--as-needed".

One thing didn't compile though: kde-base/arts (an "undefined
identifier" error, due to a missing #include). So I had to do
USE="-arts" for now.

End-result: it's *damn* fast. Well, at least compared to openSUSE 10.3.
No, it's not 5% faster. Everything seems more like 100% faster.
Well, perhaps openSUSE is "bloated", not sure. But anyway, I must say
I'm more than just impressed. "startx" fires up KDE almost in an
instant. Every application starts immediately. This is insane :D

PS:
It took me 2 days to get there though :P