I've played both, and have enjoyed Watch Dogs much much more. The only thing Infamous does better, imo, is graphics and pretty pictures you can take.
I've enjoyed WD's story much more, and there are so many more various side missions to undertake. ISS I found repetitive and boring after a while.
Overall, I think WD gives you much better value for your money.

Can't comment on the trophies, because I don't keep track of them.

agreed, I bought Wolfenstein only because I went into GS thinking TLOU:R came out 29June. The Gamestop manager talked me into it because it was on sale for 40 bucks(going to plat it, then trade it in for credit on my TLOU:R preorder). I really like just about everything about Wolfenstein, story, weapons, gameplay, setting, art style. I also love the fact their is no multiplayer, there are hordes of shooters with good multiplayer but this game has the best single player for an FPS that I have played since Perfect Dark back on the N64 (I dont play PC FPS games, but from what I have heard  about Half Life 1+2 it is probably better or maybe not) .

I would go with infamous. The funny thing about infamous is that though its an open world game its really a platformer in disguise. Or maybe I should just say that there is a new kinda genre called lite open world that are actually platformers.

Funny thing you say that, all 3d Mario games fall into semi open world category to me, especially Mario Sunshine. Or is it much more open that Mario?

Well I only got Watch Dogs, but it's a great game. People seem to complain about the length of the game, but if like me, you pick up the game and don't necessarily rush to do all the missions, but would rather prepare by getting levels/unlocking region towers etc in between missions you can easily drag out playthrough to 20+ hours. I think I invested about 15h and about 2/3 through the game. And that was with rushing missions.

Fucking annoying when someone drops into your world to hack you though, and sad thing is it doesn't even require PS+, I didn't have subscription and people still trolled me, I thought it was AI at first then realized its actual people. Scumbags.

Multiplayer is quite fun too if you get around to playing it(ended up getting the free 48h PS+ trial)

Exactly, pretty much Mario. Just takes itself a lot more seriously (or at least tries to). Its just unfortunate that they are all called open world but I really believe these games are just the new breed of "platformer" or as you put it "semi open world" I just call them "open lite". Like there is a very big difference between the open world ness of infamous when compared to say watchdogs, gta5 or even the likes of skyrim.

So infamous does a good job of giving you the impression that anything you see you can get to, but you kinda know that that isn't really the case but just never kinda mind cause its not that kinda game to begin with. Dunno if that makes sense. 

Get both, that is what I did, and ended up great that decision :)

The very first thing I did after downloading the game was to disable online intrusions. And I enjoyed the game greatly. I don't care for online gaming much, but this type of online trolling is the worst. 

Neither, buy Destiny.

I would say watch dogs, infamous gets repetitive almost instantly and the open world is completely lifeless and it's short and boring after you beat it