I don't think I've installed any new apps, but I have just updated to nightly #31, and now, everytime I start navigation, a popular tells me I need to install something from the market in order to get voice guidance... which isn't true, the voice works just fine. If I hit the install button, it brings me to Speechsynthesis Install Data by Android Technologies.
Anyone else seeing this? Was it some app? I didn't see any mention on the nightly discussion at cyanogenmod forums or in any of my quick searches.