is there a jailbreak or download yet for siri on iphone 4?
A tethered jailbreak. There is Siri on the iPhone 4, but good luck finding a download! Unlike jailbreaking tools, the Siri on iPhone 4 download is VERY illegal. Sure, it's not that bad to put Siri on your iPhone, but any site that posts it as a download is in risk of being taken down, and they are breaking the law by putting Apple's stuff for download on their site.
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I'll be happy when the mac gets some Siri love.
Don't count on it. It's less useful on the Mac, and even some of the stuff I really need is iOS only (like the TiVO remote).
Until I can get Applescript or Java to send telnet commands to a server whenever I press a button, I can't make the TiVO remote