Porting is pretty cheap. So if we talk 'smaller' games, we would talk about Indie-small. Indies don't have a big budget before developing the game. So getting another devkit and securing the publishing for another console-platform is something they think about. For PC the development tools mostly are free or inexpensive and publishing can happen over the own homepage, so here this hurdle is inexistant. Nevertheless, many recent Indie-titles were released for multiple console-platforms. So even for an indie-budget the financial hurdle to port to another platform is doable. I don't think it should be a big problem for a game that is intended to sell at full price. Still, there are a lot of other reasons for doing exclusives, but you started this thread about fanancial reasons. So I think this would only a consideration for very niche games.

Timed/Exclusive content, yeah. Full blown exclusives, not so much.

Consoles are too similar for the costs to be so high, and developers wont want to miss out on what will eventually be a huge console market with Xbox One.

It will be JP devs, Indie devs and C list developers if anything.

Maybe! Sometimes a game(or genre) doesn't "fit" in a console's "target demographic"(look Wii for example) and thus,it's easier for a Third party to avoid this machine and make the game for others.

I feel that PS consoles are the most "generic" platform of the big 3.

All genres sell well on it.

Plus, with the bigger install base i can see some single player story-driven games(maybe jrpgs?!) coming exclusive for PS4.

This is reasonable. I agree.

Yep. No argument there.

Smaller titles, possibly, if doing so results in an advertising push on Playstation products.

If you have a small team, you can work on the PS4 version first, sign a timed exclusive or permanent exclusive deal in exchange for a significant amount of advertising and you'll be good to go.

It depends on the sales expectation.

6th gen is to me the best analogy for this case, as a lot of games were only developped for the ps2 without being first party.

Let's say market shares were 10% gamecube, 80% ps2 and 10% Xbox

Can the 20% market shares not covered by ps2 cost less to port than expected revenue ?

It was only the case for big licences, so a lot of games ended up on PS2, growing its lead.

Now, let's look at the 8th gen market. Most publishers should now expect a ps4 lead. So it makes sense to think about exculivity.

Except that the port cost have gone down, because of X1 and ps4 similar architecture. And the wii U, having a very different architecture, is left on the side.

IMO, japan devs won't bother with X1, a lot have a great history with Sony too. So if the ps4 finally finds a userbase in japan, most jap devs won't think about multiplat. But western games will probably port on X1, because of the reduced cost.

No. It would make more sense to make steam or smartphone exclusive’s since there’s more money to be had there than on PS4 for smaller games.

Is that sarcasm?

It could make sense, especially for the hype of an exclusivity, but it's still very hard to tell.

About the porting cost, it will really depend on the type of game. If you are doing a little game based on Unity3D engine... porting is basically free.

Also, I think making an exclusivity is not so much based on hardware market shares. It's more about development accessibility, online policy, and online sale market share. That's why the 360 had so much more little games than the PS3, even if the hardware market share was about the same. For iphone/android again, you still make more money on iphone even if it doesn't move as much hardware than Android. So far, Sony is doing a good job, but MS has money, constraining policies for port, and a very cheap port from/to PC.