So many people are in denial over whether or not they have a problem, just look at Charlie Sheen, I'm glad Matthew recognises that he needs helps and isn't afraid or ashamed to get it. I still think it's amazing how he continued with Friends whilst battling addictions and other than some weight gain there was no difference, he was totally professional.
I don't think the cancellation of Mr Sunshine has anything to do with Matthew deciding to enter rehab, he's proved in the past that he can battle an addiction and do his job.