Isn't Alexa just Microsofts version of spyware?
Here is a related link with some info about this topic that folks should also be aware of if your going to encourage them to install on thier PC.
http://www.imilly.com/alexa.htm
I suggest that having any software(spyware) that sends ANY kind of personal info out onto the net or right to Microsoft itself is not the best thing for everyone.
Hyfi