From HMXHenry on rockband.com:
 

Hey gang,

Here's the DLC coming at you next week! Long time RB fans will remember that the Grateful Dead were the first "large pack" of DLC (a 6 pack, back in the day when 3 packs and singles were the norm) way back in March of 2008... our 16th week of DLC! Well, here we are, 115 weeks of DLC later, with a third pack from The Dead (bringing their total count up to 18 tracks) along with 2 singles from RB newcomers The Smithereens. Enjoy!

Available on Xbox 360, Wii and PlayStation 3 system (May 18):

Grateful Dead – “Beat It on Down the Line” +
Grateful Dead – “Cumberland Blues” +
Grateful Dead – “Scarlet Begonias” +
Grateful Dead – “Throwing Stones”
Grateful Dead – “Touch of Grey” +
Grateful Dead – “U.S. Blues” +
The Smithereens – “A Girl Like You”
The Smithereens – “Only a Memory” +

(All tracks are original master recordings)

(These tracks will be available in Europe on PlayStation 3 May 19)

These tracks will be available for purchase as “Grateful Dead Pack 03,” as well as individual tracks on Xbox 360 and PlayStation 3 system, and as individual tracks only on Wii. Tracks marked with “+” are also available for download in the family-friendly LEGO® Rock Band Music Store.

Price:

$1.99 USD, £.99 UK, €1.49 EU (160 Microsoft Points for Xbox 360) per track
$9.99, £4.99 UK, €7.99 EU (800 Microsoft Points for Xbox 360) for “Grateful Dead Pack 03”
$2.00 USD (200 Wii Points™) per track

wow i forgot how much Dead RockBand has until now.

Rock Band releases have been terrible for me for about 2 straight months

Oh man I sure do hope they release another disturbed pack soon.

Nice release this week, but god I really don't want to keep buying DLC. I've been at a point where I feel like I have enough to last me forever for a while now. I already have most of the songs I would ever want. DLC is a money sinkhole. 
 
That said, I just bought two Jonathan Coulton songs yesterday.  :P

No thanks.