Rhapsody, Therion, Nightiwsh, Borknagar, Amon Amarth, Kreator, Behemoth, Sonata Arctica, and Symphony X all have albums coming out this year. My bet is all of them will be better. This is an improvement for Slipknot, but it's still rather boring and the shredding solos are average (For shredding solos).
And the Katatonia, Death Angel, Dragonforce, Finntroll, Dark Funeral, Edguy, Kataklysm, Deicide, Vintersorg, My Dying Bride, and Iced Earth (Think that came out this year) are also all on part with or better than this Slipknot. These already came out, I should clarify that.
Tis a great year to be a metalhead though.