From HMXhenry at rockband.com: 

DLC Week of 12/21 - John Lennon's "Happy XMas (War Is Over)" and 7 EU Singles

Hey gang,

The holidays are almost upon us, and there are only two weeks of DLC left in 2010! John Lennon and the Plastic Ono Band will help us wrap up the year with Happy Xmas (War Is Over) and they'll be joined by an assortment singles from international artists. Be sure to take a closer look at the EU singles, as I'm sure many people will know the Caesar's track, but there's some other gems in there. And don't forget about the Rock Band Network tracks listed below! There are tons of great songs on all three consoles from bands of all types. 

Available on Xbox 360, Wii and PlayStation 3 system (Dec. 21):

John & Yoko, The Plastic Ono Band – Happy Xmas (War is Over)
Anaïs – “Peut-Être une Angine”
BB Brunes – “Dis-Moi” X
BAP – “Verdamp Lang Her”
Wir sind Helden – “Nur ein Wort”
Linea 77 – “Fantasma”
Litfiba – “Proibito”
Caesars – “Jerk It Out” X

(All tracks are original master recordings)

(These tracks will be available in Europe on PlayStation 3 system Dec. 22)

These tracks will be available for purchase as individual tracks on Xbox 360, PlayStation 3 system and Wii. Tracks marked with “X” will include Pro Guitar and Pro Bass expansions for $0.99 per song.

Price: 

$1.99 USD, £.99 UK, €1.49 EU (160 Microsoft Points) per song
$2.00 USD (200 Wii Points™) per song
$0.99 USD (100 Wii Points/80 Microsoft Points), £0.59 UK, €0.79 EU per song for eligible Pro Guitar/Pro Bass upgrade

 Tutankamon - "Starting to Appreciate"
Skizoo - "Dame Aire"  

Jerk It Out's a sweet song. Never heard the rest. I guess one good song is better than weeks when there are no good songs. 
 
(Yes, I haven't heard these songs, therefore I deem them "bad")

Not to sound like a grinch, but I hate holiday music. If they were gonna put any in, I'm shocked to see no Wizzard.

Added an update to the OP.  Two more songs are coming out.

People may know Jerk it out from the very first iPod shuffle commerical way back when.

If they really wanted to make a holiday DLC, they need to get Little Drummer Boy in there with Bing Crosby and David Bowie.  I can see it already, split vocals and piano with drums only.
 
[edit] Oh, there is some bass in there too.
  

I miss the days of free Christmas DLC.  Especially considering that holiday songs aren't likely to be played much outside of about 2 weeks out of the year.

I misread the title for "Lemon" for a moment.
 
I miss Lemon Lens

" I misread the title for "Lemon" for a moment.  I miss Lemon Lens "

Rather have Paul Mccartney's Wonderful Christmas time than anything by Lennon. But then I can't stand anything Lennon did post Beatles. 
But then I'd rather have Slade and Wizzard than what they've been putting on for the past couple of weeks.

how about no Christmas music!
but, I also work in a retail store, so I hate all of it.
Well, except for the predender's version of "Blue Christmas" ...we don't play it there.