The final word is that Vince Carter is definitely out, he suffered a mild concussion (not just a mouth laceration as reported) - he woke up 'woozy' this morning and will not play. Mickael Pietrus will start in his place and there is a possibility that Josh Childress gets some playing time tonight.
Channing Frye also was diagnosed with a mild concussion and was held out of yesterday's practice. He is expected to start and play tonight.
Check out Seth's write-up over at the motherbase.