Strange system responsiveness issues with 5.1-CURRENT

Hello (World).

I've recently moved from FreeBSD 5.1-RELEASE to 5.1-CURRENT (from
September 21) and noticed some strange changes in my system
responsiveness (using identical kernel configs).

Some applications, like games/fuhquake, Quake3 and SETI seem to run
faster (I get better FPS in games and my SETI WU crunching time has
slightly decreased). However, in many cases, the results have been less
then good:

Starting applications (XFree, Evolution, Mozilla, OpenOffice, games)
takes a noticably longer time than it used to, I'd say that Mozilla
Firebird load times have increased by about 30-40%. I can also now see
"jerkiness" in switching between applications. When Alt-Tabbing between
Firebird, OpenOffice and Evolution, the windows appear half-drawn for a
second or two.

When I play music (MP3 and/or OGG) in XMMS and try to drag the position
indicator forward/backward to go to that specific part of the track, it
now takes 2-3 seconds until it actually "switches" to that part of the
track and starts playing it, even though with 5.1-RELEASE that was
happening instantly.

Am I doing something wrong or is this to be expected ? Unfortunately I
have no webspace to post my dmesg and kernel config on, but if any of
you people want them, I can send them attached to a private mail.

Sincerely,
Dan Naumov