Not too much interest in visual novels here, but apparently an “iOS port of Steins;Gate is due out later this month”:http://www.famitsu.com/news/201108/17048607.html.
3000JPY non-universal app for either iPhone or iPad, text heavy-game translates very directly to prohibitive cost for an iPhone app (1 USD = 76.5 JPY) and zero chance of localization, so definitely not picking this one up myself.
Personally waiting on Amazon tablet, I think. Although sadly the region locking is actually, seriously, making me wonder if an iPad wouldn’t be a better idea.