The general feeling from Wii U eShop developers seems to be that Nintendo is a pretty decent company to work with. Cloudberry Kingdom developer Pwnee Studios has reinforced this viewpoint in an interview with Aussie Gamer, where company co-founder TJ Lutz said:
Nintendo has been great to work with so far!
We were raised playing the NES and SNES, so when we got the chance to develop our game for the Wii U, we were pumped! We really haven't had many issues with Nintendo, and they have been very helpful whenever we have had a problem.
In terms of getting the game onto the eShop, it has gone pretty smoothly. We presented the game to Nintendo, they liked it, and they said we should go onto the eShop. All we had to do was agree!
You can read our own interview with the studio here.
We've seen an avalanche of new indie titles confirmed for the eShop, including Scram Kitty And His Buddy On Rails, Another Castle, The 90's Arcade Racer and Cryamore. The system is becoming a real haven for small-scale developers, and when you hear studios talk so highly of Nintendo, it's pretty obvious why.