madonna and christina is neither better nor worse (well christinas is better than the debut of course)...they´re evolving, true stars IMO.
artists that´s better than before:
justin timberlake (yet i wonder how it would be w/o timba..)
T.I.
beyonce (in large parts i prefer b´day to DIL, suga mama is the ish to me!)
evanescence
j.lo
RHCP...bringing funkyback....too!
worse:¨
AVRIL LAVIGNE...where do i even begin? lol
pharrel (almost dead right now, compared to the hype a couple o´years ago)
nickelback (from bad to shiteous)
akon (the singles from the debut were decent, now he´s making me

jay-z
r.kelly(ugh...the pedofile could at least do decent music BITD!)
METALLICA (could easily be the worst downstep ever....from masterpieces like master of puppets and justice for all down as far south as st. anger!)