One app, called Siri for Android is a hard link to Google’s voice controls while another, called Speerit is a Korean clone that purports to connect to Apple’s servers (which is untrue).
Whether you believe these apps should exist on the Android Market or not, its clear that there are enough new users out there who will fall for some of the oldest software tricks in the book. A word of advice: if it’s called “Siri” and it runs on Android, it’s probably not real.