ah ok now with the logo on it I understand
If you have your image as an illustrator file you can make paths of the letters and the logo by shift-clicking the objects/text you want have in maya and press ctrl+shift+o. now select the white box and delete it. Save the file as an AI uncompressed file and then import it like I told you. That would work. But I think bendingiscool's way is more comfortable because you have the color information with it cause it's a pic and not a vector information.
hmm, but now I have a question. Everything which is black is transparent in alpha channels, isn't it??? Because when I make my adjustments for the discreet keyer in combustion the alpha matte is always: black: transparent, white: footage. Haven't worked with photoshop for too long