Most Popular Game To Record and Upload?

Just upload what you want to play and enjoy. Don't play black ops II etc (unless you enjoy it) to go with a trend.

People will respect you if you enjoy making your video's. And they will enjoy it too.
Popular games played and shared on youtube: Minecraft, Black Ops II, Hitman Absolution, Hitman Blood Money.
For starters, Minecraft & Hitman Blood money are cheap for what they are, very enjoyable and great content for your viewers.
Games that are popular to play? For shooters its obviously Black Ops 2, BF3, Etc. Strategy games obviously gonna be the the brand new Starcraft 2 HOTS, MOBA games like League of Legends, Dota 2 etc.

A lot of new games are popular like tomb raider, Sim City, etc.

And like a lot people are saying, Minecraft.

I know a lot of people are saying don't play those games you wont stand out, which is true as you're going to have the hardest time competing with literally 1000s of other channels. But if you can find a way to make your channel different from all the rest, then I say go for it, for example, commentary, if you're fun and entertaining with your commentary you'll stand out.
Well I just got a new pc, a Dell Inspiron 15r Special Edition. And I'm looking to play some games for my YouTube channel because now they hopefully wont lag. Do you know any games that a lot of people are watching? Thanks :)
Tomb Raider is a huge one ATM.
I do have to encourage you to do the games you love because if you dont enjoy playing it people will know and it will come out in your videos.I generally like to watch different things then new games all the time. Vareity can be a good thing for example a lot of channels only focus on console or minecraft but there are a lot of interesting indie games and flash games as well.views are great but i would take vareity channel and a unique blend of gameplays with a few less views but a whole lot more fun because your doing what you love not just what people want to see.