Starcraft 2 or assassin's creed brotherhood.

Second Life?

I think TNT has kind of run its course. But if it has to carry on, I think a bi-weekly schedule is far more interesting than a weekly one. Not enough interesting multiplayer games come out often enough to justify a TNT every week.

Marvel vs capcom 3! Or MK vs DC Universe

*Starts looking through games*
I know it's a shooter but I wouldn't say no to Gears 1 or 2.
-Forza 3
-L4D 1 or 2
-Blur *Enjoyed being part of that. Was alot of fun*
-Soul Calibur IV
-MK VS DC *Maybe a little irrelevant no MK9 is almost out*
- BURNOUT PARADISE!!!

" League of Legends! Free-to-play, low PC requirements, tons of players. There's nothing more perfect. "

Just throwing a few ideas out, some already mentioned, and some that might not work on their own.
 

• The Ship *
  
• Burnout Paradise (including PC)
• Altitude **
  
• Battlefield 1942 ***
• Battlefield 2 ***
• Half-Life 2: Deathmatch ***
• Mount & Blade: Warband
• Worms Reloaded

 I'm loving indie games at the moment, so that's going to be my suggestion. Mount & Blade Warband and Plain Sight were already mentioned, and they are great. I'd like to add Gratuitous Space Battles, where multiplayer requires no concentration at all, because you don't play. You just build your fleets and let 'em fight it out in glorious 2D.
 
Another cool thing would be RTS games like DoW2: Retribution and Men of War: Assault Squad. They're great for spectating, but do require a lot of concentration. You'd have to sic someone like Brad on them. Total War: Shogun 2 could be worth a shot as well. 

" *Starts looking through games* I know it's a shooter but I wouldn't say no to Gears 1 or 2. Forza 3 L4D 1 or 2 Blur *Enjoyed being part of that. Was alot of fun* Soul Calibur IV MK VS DC *Maybe a little irrelevant no MK9 is almost out* "

NBA 2K11! 5 on 5 team up mode! 
 
(Like that'll ever happen. Oh well, I can dream.) 
 
Rock Band 3!

Tetris for the PSN is a pretty cool as someone suggested earlier on.

LBP2. Didn't see that one coming, did you??

" Rock Band 3! "

You don't know Jack would be fun. Not many people playing together during a multiplayer session but everyone watching could follow along. 
  
Old school flying sims such as Tie Fighter could be fun. Hard to set up though, methinks. Maybe that Snoopy game on XBLA would be fun?

" If the server is still up, Blur.  That game is complete anarchy online. "

Some GTA IV Cops n' Robbers would be awesome

My vote goes to Monday Night Combat. Mostly I just want an excuse to play it some more.

Mario Strikers Charged... insanely fun offline multiplayer and online. Defiantly the best Wii online game to-date. :)

Here is what games i would like to see for a TNT 

nail'd 

Banjo Kazoiee Nuts and Bolts, that would be crazy

Gmod. The goal is to crash the server as quickly as possible.

Maybe Super Smash Bros Brawl, only for offline multiplayer. Online is laggy as hell.

You Don't Know Jack
Need For Speed: Hot Pursuit 
Alien Swarm 
Rock Band 3 
Super Street Fighter 4
Marvel vs Capcom 3

Minecraft
 
maybe some Warcraft 3 DOTA action :)
 
or some Command and Conquer Red Alert 2

Bionic Commando would be awesome.

I would love to see next StarCraft 2 Norm vs Brad battle. The last one was really epic and fun to watch. Of course it is boring for people who don't play RTS games, but you can say this about every game out there. Nobody is playing and loving everything. So yeah, some StarCraft 2 action please!

GTA 4, Assassins Creed Brotherhood, The Darkness, Worms 2

Dawn of War 2 Retribution

- "Half Life 1 Deathmatch" (maybe as a throwback when Episode 3/HL3 gets announced ... similar to what they did with DN3D)... anyhow, it's insanely fun.
 
- Someone earlier said "Worms 2" ... this could be fun to watch.
 
- "Red Dead Redemption" ... I want some more!

If the servers were still going I'd say Chromehounds,but considering that's not the case.....MvC 2??

I would be down for some Counter Strike.

Split/Second is pretty rad. Or more NFS: HP, that's a lot of fun to watch and play too.

Worms!

I have to agree with Worms, that could prove to be very funny.

Mortal Kombat....when it comes out in April! Assassin's Creed Brotherhood is awesome! I'm still waiting to poison Ryan's character on air just to hear him shout 'OH NO!"

" Banjo Kazoiee Nuts and Bolts, that would be crazy "

" NBA 2K11! 5 on 5 team up mode!  (Like that'll ever happen. Oh well, I can dream.)  Rock Band 3! "

Uno!

assassins creed brotherhood,  
umk3 
mk2 
doa4 

One of my favourite TNT was Madden. I know with this audience it would be kinda stupid to ask for more sports games but more sports games please.

Burnout paradise would be awesome.

I would love to see Smash Bros. get played. If only it had decent online.
 
Just any action or fighting game would be good. Definitely look back at some older games from this console gen, or classic games for PC (the Quake and UMK 3 TNTs were my favorites)

AI War: Fleet Command 

How about the great old arcade beat-em-ups that have been re-released for download like Teenage Mutant Ninja Turtles 1989 Arcade, TMNT Turtles in Time, Final Fight, and X-Men?

I know you did it not too long ago but AC: Brotherhood was great to watch. Also if you go back and play Halo 3 with action sack playlist you get a load of crazy variants that are really fun to play.