I own SMB & Jamestown on Steam, Cave Story & BitTrip Runner on WiiWare... - Edit 2
Before modification by Zalis at 14/12/2011 01:23:23 AM
Super Meat Boy is supposed to be a superb platformer, with tons of unlockable characters.
Yes - tight controls and stiff difficulty make it a frustrating, yet rewarding platformer. The sense of humor is strange, but somehow charming. Expect to die a lot; don't play for long periods.
Cave Story+ is an amazing... I guess you'd call it a platformer, except it's really bizarre, and has a bunch of cool, unique guns with multiple endings.
The WiiWare version is pretty neat, though I got distracted before finishing. I'd second your endorsement from what I played of it. It's basically an indie metroidvania title.
I haven't heard of the others (Bit.Trip.Runner, Shank, Jamestown and Nightsky HD), but they look interesting.
BTR is basically a rhythm platformer. You jump, duck, etc, to the music to avoid obstacles and beat each stage.
Haven't played Shank, GSB or NightSky.
Jamestown is a pretty sharp little bullet hell shooter. I've played it with a partner and it gets even better with extra players. The music, quirky story and superb pixel art make it a tight package. My only complaint is the length, which is a scant 5 stages. Difficulties and unlocks help, but I'd still like to see more.
Minor caveat- in order to get GSB and Cave Story+, you have to pay at least the average price. At the moment, that' $5.01, still a total steal.
The price of these usually drops over time. It was $4.57 when I looked earlier, but now it's back up to $5.20. Still, that's a chump change difference.