I say it all the time in casual speech. However, I think it has no place in formal speech. When I’ve heard reporters say it (and I have, more and more frequently), I think it represents a very slack attitude and sounds very unprofessional. I haven’t seen it written in a formal news story, but I suspect I’ll have an apoplectic fit when that day comes.
When I hear leaders, politicians, and other supposedly-important people use it in public speeches, I feel very discouraged.
You know, I spent a happy couple of moments contemplating the inflected forms of “wanna” (“I wanna learn”, “she wanza learn”, “he wanneda learn”…) before I realised you meant inflected as in stressed or emphasized. :smack: