By king, I mean (obviously) the PS2.

Better sales? While I think the PS4 might get to +100 million, I also believe the industry has shrunk. We can see it with the 3DS. Smartphones might not kill gaming, but it's just gonna make the market much smaller. BUT there's also the possibility that the Xbox/Nintendo fans go to PS because it offers them a better option, which is true. It's happening with a lot of Xbox fans (If what I've been seeing in the community is true).  And there are multiconsole owners. This should make it a little below PS2, like, 130 million PS4 vs 155 million PS2. I'm not that good with predictions but I think this looks reasonable... 

Game quantity? PS4 wins, easily. Indies. That's it.

Game quality? I can't give you my opinion on this one, not a good one at least. I was really young when I had a PS2, so I thought every game was awesome, and I didn't get some amazing games it had. I mean, I never got SoTC, KH, FF, MGS, and many many awesome games. But some of my favorite games are there (the ones I played), like GTA: San Andreas, DBZ: Budokai Tenkaichi 2, Okami, some Tony Hawk games, and I know there were more, but again, I was young. And the PS4 has this modern 3rd party devs that I just dislike. Well, not the devs, but they're business practices. Microtransactions, loads of DLC, pay-to-win, rushing games, sequels and sequels and sequels, ripping off, too much. Also, paying to play online. But I'm not saying everything is bad. There's KH III, Metal Gear Solid V, FF XV, Uncharted 4, and many more to come.

As a device? PS4 wins easily again. I don't feel like explaining this.

What else? Fans? Well, right now, the PS fans should be celebrating like there's no tomorrow. I don't know if that's good or bad.

Maybe the PS4 will dethrone the king, Sony has just begun and they're outselling the Wii. Dat fad! 

But what do I know? I'm just a Nintendo fanboy...

I thought u were a mac and cheese fanboy... You can't be both!!!

I think all ps4 needs is their first party exclusives... They already got third party and indies on board, just a bunch of awesome first party IPs and its gg

I'm secretly a spaghetti fanboy...

What a twist!

I'm thinking two things.

Games (which obviously we'll see some big names over the next couple years)

The wild card - VR 

Sony has been working on virtual reality for quite some time now and I expect to see it as some sort of add on or bundle for the PS4. If it's a hit with the consumers and it's done right with an affordable price, it can take off like how the Wii did in the beginning with it's motion controls, then we could see some explosive sales.

They need Nintendo and Microsoft to go bankrupt soon, but that's not going to happen.

Exclusive MLG level shooters like the Xbox and cartoony, kiddy games like Nintendo.

Good games on every genre (many)

It basically needs a build in time machine that can transport it back to the time when there weren't so many rivaling entertainment options available.
 The PS4 will never sell as much as the PS2(I'm still doubting even the 100m) but that's not the system's fault and there is nothing it can do.

The PS2 didn't enjoy that.