Microsoft doesn't approve every piece of software I install on my computer, all Windows does is ask if I'm sure I want to install. Last I read, Windows is still on something like 90% of computers in the world. This tells me that the average computer user is used to taking responsibility for their own actions. If I started a forum post saying that it's Microsoft's fault I installed malicious software, I'd be laughed out of the forum and most likely black listed from every tech sight for such blatantly rediculous statements. Now, considering the most popular computer OS in the world has been treating adults like, well, adults for years, I don't really expect anything less of Google with their PHONE OS. It's my computer, it's my phone, it's my personal data so it's MY RESPONSIBILITY!
Bottom line: If you feel you need your apps prescreened before they get to the app store, get an iPhone. If you want a device more like your pc that gives you more freedom INCLUDING the freedom to install one of many virus scanners in the Market, get an Android and take responsibility for your own actions.
P.S. Apple also screens apps to make sure nobody's putting out low quality or vulgar/pornographic apps. Thus far they've done so well at this screening that you can currently download the Playboy and the iFart apps among others. I truly hope they're doing better at screening for malicious content than they are for vulgar/pornographic content, especially given the fact that everyone with an iPhone seems to think Apple doesn't make mistakes.

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