Really wide variety of games including great library of downloadable classics and indie games and big user base thus better online experience playing with friends etc

Also simple user friendly interface and quick updates.

Cause to the general consumer you get the best of what the PS3 can do (play HD Games) and the Wii (Causal /Physical type games) with Kinect, plus, a bunch of really easy to use apps for TV/Movies/Gaming/Sports/etc.. Its a fun package to play with kids and get the whole family to play - Kienct, then turn on a watch a cool movie, then, when the kids have gone, play some fancy HD games.

If you like your others systems, cool. But as I see it, its best package for all three.

^this... what Zappykins said
and to me the XB1 is just improving on that versatility I'm looking for on a console....

I don't have kids yet... but I have a non gamer wife and I like to be the kid when it comes to new tech.... yeah I'll admit it I can spend hours on fruit ninja Kinect and never get board lol

Price-at launch it was $200 cheaper than PS3, and for the last 5 years has had a $199 model whereas PS3 has yet to reach that.

Xbox Live-even though its the only online service that costs, its considered the best and worth the price.

Exclusives-Halo/Gears/Forza/Fable are all critically aclaimed series

Multiplats-not true anymore but for awhile it had the best version of most 3rd party games.

Controller-the most comfortable controller on the market

Im not an Xbox gamer and dont own a 360, these are just some of the things ive seen/heard as reasons people prefer 360.

Halo.

I think what Dan is  saying is: "Why now?"   When it was the only option, and the PS3 was making mistakes left and right it made a lot of sense.  But now in 2013 what great game is coming out now that would make you buy one when no other game before was able to convince you?

To me, it's nothing. (Not to sound like a troll but continue reading)

I don't own a 360 as I find it's value doesn't justify a purchase. However, I enjoy their Halo games which is why I own all the Halo games. I buy their games but I just borrow a 360 from friends and family.

This is something I'm doing currently for 360 & Wii U, (and possibly Xbone), where I'll like some of their games but not enough to purchase the system. So in the mean time I'll purchase the game and find the system to borrow. As well, I purchase games that I know will be harder to find down the road so at least i'll have the game because you can always get your hands on a console but not always for the games. I'll wait for the 360 and Wii U to go down to $99.

I guess if I were to give an answer for this thread, then it'd be Halo.

Originally, people bought it as was cheaper and had a decent set of games. Now, it probably sells for the same reason. Most of my friends ended up buying the same console, just so they could play together. Many of whom got Xbox 360. I choose not to because it didn't have the exclusives i wanted and i didn't want to be forced to pay to play online (something i rarely use anyway). Also, RROD was a huge problem which swayed over to paying extra for the PS3 (i bought a PS3 slim in late 2009, Xbox 360 slim didn't exist yet), what i didn't know back then was that i liked the PS3 exclusives far better than the Xbox 360's, i just knew PS3 had more variety. I didn't even realise that Uncharted was such a great series before i got PS3. Even now, i don't regret missing out on Xbox 360 because of all the great games on PS3. 

Yep!  There were so many 1st party franchises I loved from Killzone, Resistance, MAG, LBP, Demon's Souls, MGS4, Uncharted, Warhawk, InFamous, and Heavy Rain that I practically had no time for any third party games.  Battlefield and Read Dead Redemption were about it!  Just now I am making up for that with steam sales!

So to say what Lt. Dan said, with the The Last Of Us, God Of War, and Beyond Two Souls coming out this year the trend has not stopped on PS3 in 2013.  On 360 there is another gears of war game (The fourth this gen!), and that's about it while next gen is right around the corner.

Why would anyone choose a 360 now?  It is something I cannot rationally answer myself...

As said before.

Games - Multiplatform titles are always there. If your into shooters you still get the exclusives like Gears of War, Halo, and Call of Duty timed DLC. MS is still throwing the 360 a bone this year by released Fable Anniversary HD this fall/winter. You can't discount all the games released the last 8 years either.

My friends have it - People buy 360's to play online with their friends. If all their friends have 360's then they will most likely buy one to.

Cheaper - The XBox has always been cheaper then the PS3.