Recently I found that in Cordova it is possible to obtain user's phone number (cordova plugin link).If Cordova can do that, than Appcelerator should too.
How can I do that in Appcelerator Titanium?
I made a module a while ago and uploaded it to github: https://github.com/m1ga/com.miga.gsm
this will get you some of the fields the cordova plugin gives you. It will read the phone number but as mentioned in the page you've posted it's not reliable.