Quip is a new Twitter client for the iPad which is absolutely beautiful. I'd even go as far to say that it might just be better looking than Tweetbot. It's main unique selling point is the way it focuses more on conversations in Twitter, enabling you to quickly look at replies and mentions on tweets. It's done this very well, better than any other Twitter client I know of.
Another feature which is small but one which I love, is how it shows how many retweets a tweet has got right on the timeline, instead of having to tap a couple of times to see retweets like on other clients.
Image viewing is also a pleasure, with the ability to sift through images quickly in a gallery like format.
With it being relatively new there are some bugs and it could be a lot smoother. Also it's no where near as powerful as Tweetbot as of yet. Quip is quite basic but it should be adequate for most. If you're a power user on Twitter, going through a ton of tweets, opening links constantly, saving them to read later and so on, you're better of sticking with Tweetbot. I highly recommend trying Quip out though.