After the fiasco of the DIVX Web Player 2.0, forcing all online movie watchers to downgrade to 1.x, the new DIVX Web Player 2.1 finally plays Megaupload movies again!!
So no more need to install an old DIVX player and keep it from updating anymore, noobs can now let themselves be led by their browsers instructions to get the DIVX plugin installed and not have to bother.
On the other hand, while im delighted that the new DIVX Web Player plays megaupload links again, my experience with it was not so great on my main movie watching computer, which runs an old quite outdated windows XP. It worked for a day or 2 and then it mysteriously stopped working, trying to play any DIVX on a webpage just froze Firefox everytime. i uninstalled and reinstalled the DIVX 2.1 but the problem remained. After that i had diffictulty uninstalling it again, i had to exec "msconfig" and turn off some divx related services and reboot to be able to uninstall..... then i just reinstalled 1.5 and everything was great again. So i personally recomment that you still stick to 1.5 or 1.4 for now (get it here), that might save you a few headaches.