I have an '07 as well, and I have to say…..the BT voice recognition in these vehicles is pretty lame. I'm not sure if the newer models are any better, but mine has been frustrating me for the last 4 years.
In comparison, my wife's 2010 Nissan Versa has an incredible BT system….the voice recognition and controls are fantastic!
The mic in the RAV is up next to the dome lights as previously mentioned. My wife has a fairly high pitched voice, and I notice that it doesn't work well for her no matter what we do. As long as you speak clearly and project your voice towards the roofline it works fairly well.