D2 for me. Skid Row the only other competitor to that amazing album.
I'll just go and rank em all since I like most of em and know all of em
1. DANGER DANGER- DANGER DANGER
2. SKID ROW- SKID ROW
3. SIGNAL- LOUD AND CLEAR
4. XYZ- XYZ
5. BABYLON A.D.- BABYLON A.D.
6. GIANT- LAST OF THE RUNAWAYS
7. EXTREME- EXTREME
8. VAIN- NO RESPECT
9. SHOTGUN MESSIAH- SHOTGUN MESSIAH
10. BADLANDS- BADLANDS
11. BAD ENGLISH- BAD ENGLISH
12. PRETTY BOY FLOYD- LEATHER BOYS W/ ELECTRIC TOYS
13. JUNKYARD- JUNKYARD
14. BLUE MURDER- BLUE MURDER
15. TORRA TORRA- SUPRISE ATTACK
16. TANGIER- FOUR WINDS
17. ENUFF Z' NUFF- ENUFF Z' NUFF
18. MR. BIG- MR. BIG
19. DANGEROUS TOYS- DANGEROUS TOYS
20. BANG TANGO- PSYCHO CAFE
although now that I think of it, I'd have liked to see on this list Pink Cream 69 - S/T, Lillian Axe - Love and War, Leatherwolf - Street Ready, Treat - Organized Crime, Motley Crue - Dr. Feelgood and Diving For Pearls - S/T. 1989 was definately one of the best years ever, if not the best.