I don't get the problem of having Android apps running on WP. And I always feel like hitting with a chair the person that says "Android apps = Malware". That's the same that saying "Windows programs = malware" and equally stupid.
Of course there's malware on Android. That's the price you pay for having an open source OS. Just like there's Malware on Windows. In either case, you only get the malware if you're reckless in your use of technology. If you try to pirate apps, meddle with those shady third party stores or if you're just downright dumb that download anything that has the name you're looking for in the title and don't bother to look at who's publishing it.
At any rate, all Windows Phone Android apps would come from the Windows Store anyway. Which means, they'd be still checked for malware and all of that.
The thing is: WP developers aren't committed to the platform. Microsoft needs apps. They simply have to find a way to bring those apps in. Is it a sign of capitulation of WP? Yeah. But then again, it's not worse than stale sales or inability to grow market share. Because ultimately, Microsoft shareholders will NOT allow Windows Phone to continue for much longer. If they can't grow its market share to the point of at least no-losses, they'll kill it.
What do you prefer? WP living with Android apps, or WP dead? That's the question you should ask yourselves.