This would be in the fantasy version of the series that exists in your head?
He was okay near the beginning but, near the end Tennant's Doctor was more ticking off items in a check list rather then an actual characterization.
Act hyperactive -Check
Say "Allonsy" -Check
Say "I'm so sorry" - Check
Break out the crying towel - Check
Pull stupid faces - Check
And sadly a ramped up version of how he was near the end is most likely what well get. Heck, that's what we got when Tennant guested on The Sarah Jane Adventures.
Did you think the most popular and succesful Doctor of all time wouldn't be back if they were doing a multi-Doctor story for the Anniversary?
So, Tom Baker is going to be in it then?