Right.......... Well I've seen a TY vid on Black Flag  on the TV and there rarely had any frame drops. Plus a trailer too. And YT compresses everything but whataver. Still getting it.

And I could always get this if I wanted DLC, which I don't mind if I do/don't. :

AC1 and 2 and Brotherhood and Revelations were out before the Wii U...

Not intrested in the American revolution, or the French unity one. I like Pirates.

So  I don't see the point in your statement lol.

So you want to sell your Xbone because of a bigger user base? I wouldn't say that's even a good excuse to sell it, you already have an Xbone that can play cod and all the games you listed so what's the point? but hey if you really want a PS4 then go for it.

Short Answer: No.

Long Answer: Based on your priorities you need to consider 3 things.
1. CoD advanced warfare has more preorders for Xbox One than any other platform. Hence, it is logical to assume that the largest player base will be there. There is also the early DLC for xbox platforms, and platform parity.
2. Exclusive Games. There aren't any great PS4 exclusive games. If you weren't able to fall in love with Gears, Halo, Titanfall, Forza Horizons, Left 4 Dead, or the future prospects of Sunset Overdrive, Halo 5, Quantum Break, Scalebound or Crackdown, then you won't fall in love with Playstations breif collection (of Infamous and DriveClub).
3. Timing. Xbox One is just getting warmed up at this stage, with a constant supply of exclusives for the forseeable future. PS4 doesn't get any more notable AAA exclusive games until the end of 2015 (with Uncharted 4, and Bloodborne), in fact, no more are arrving this year.

You have to ask yourself why you are buying it. The only reason would be a graphical upgrade. I respect any decision you choose, so long as you have fun, but do consider these points.

Doesn't matter which game you thinkk is a ghost town, especially older games.  In the next 3 months, close to 3 million XB1's will be purchased.  The userbase will go up dramatically.  Because the console is less than a year old, the userbase will literally increase daily in the next 2 years at a significant rate.  No reason to dump any system.  If you had said that you really wanted to buy a PS exclusive title that you just had to have, it would make more sense.

You really don't see the point in my statement? The OT already has a 360 and a XBO... why should he be interested in the WiiU-versions of AC3 + AC4, which perform even worse than the 360-versions and lack content? He can already play most already released AC games with that combination and will have access to future AC-titles, no matter if he keeps the XBO or gets the PS4 instead.

The WiiU won't probably even get AC:Rogue.

OP:

I really think you should keep your Xbox One. It has a lot of games and Cod Advance warfare will have huge amount of players. If PS4 has slightly more....it doesn't matter.
I see no point in buying the PS4 just because it's the cool-er thing to own and play.

I would do it, sounds like the only thing you are missing is Halo... and if your not into it who cares? PS4 getting COD DLC a month late is that really even a selling point for the XB1 version? I mean it's a bloody month... if it was 6 months maybe but 30 days? Hardly worth calling a timed exclusive lol

Go with a PS4, you will be glad you did.

He is in Aus, which has a small X1 playerbase, so for online competitive gaming he's better off with PS4 as long as it's not expensive. Then re-buy the X1 down the line.

If he was in the US it'd be a no brainer to keep the X1 imho.

So much wrong with this I don't even know were to start...