They don't mention Tweetie for Mac, but I imagine that will become free too. Clearly the Mac client wasn't the focus of the acquisition, but it's also great software in my opinion.
I deliberately have not paid for Tweetie for Mac. I love the Fusion Ads. They're incredibly useful and beautiful.
You can re-enable ads in preferences if you buy tweetie and want them back.
I'm glad Loren will be joining the team and there will be a Twitter for iPad, but what is the implication for all the 3rd party applications if Twitter has official versions on these platforms?
Is it really any different? Consumers will still buy the client that best fits their needs.