Updated. Again. Damn, I love the internet.
10. Metallica - Ride the Lightning
9. Sepultura - Beneath the Remains
8. Anthrax - Spreading the Disease
7. Destruction - Infernal Overkill
6. Artillery - By Inheritence
5. Possessed - The Eyes of Horror
4. Vio-Lence - Eternal Nightmare
3. Overkill - The Years of Decay
2. Dark Angel - Darkness Descends
1. Exodus - Bonded by Blood
That is a kickass thrash line-up. If I had a radio running, that would be playing every Thursday. THRASH THURSDAY!!@~#~
EDIT -- Updated again! Artillery for the win. I'll count January 1990 as the 1980's since they probably pushed for a 1989 release! :p
EDIT -- Updated. Again. Sorry Slayer, yer off the list. Anthrax replaces you!