Hmm...
I think before you can define an "I.T. Architect" you need to have a definition of "I.T." that is agreed upon.
Even though it's a concept that has been around for longer I have yet to find any two companies that see it identically, occupying the same role and functions.
That said even though I have my own solid definition of "I.T." I haven't the slightest idea what an I.T. Architect would be and/or do. It sounds like a buzzword to me.