Fresh from playing Steve Jobs in a biopic of the Apple founder’s life, actor Ashton Kutcher has been talking about technology at the CTIA conference. Kutcher is also an investor in tech startups, but it’s his views on Twitter that are making headlines this morning. “Twitter’s experience has changed for me, pretty drastically,” he said. “It used to be sort of a personalized experience for me, a really personal experience that I could share… For lack of a better verb, I think the media kind of fucked it up. I think media companies came in and just pounced on it and I think that the signal-to-noise ratio kind of stinks — people selling shit that I don’t want.” Ouch. And there was more: “I think retweeting hurt Twitter the most. It created a ton of noise in the system that took away from some of the value.” A valid criticism? The more Twitter grows, the noisier it becomes – and with the company having cracked down on Twitter apps made by other developers, its challenge is to ensure its own website and apps get features to help people filter that noise.