Please stop using the word practicing Muslim and non-practicing Muslim. There is no such thing as practicing Muslim or non-practicing Muslim. To be a Muslim, a person MUST PRACTICE the Sunnah and follow the Law of Allah.
If a person does not practice then he/she is not a Muslim. How can u say u submit to Allah then you dont follow His Law?
I just read a very meaningful article. Its about Muslim, Kafir, Munafiq etc.
Read this beautiful entry at http://saifulislam.com/?p=5879#more-5879
Please, I just hate people using that word.