Definetly not, releasing a GameboyHD at this point is = suicide.
1st-Nintendo would only be eating its own 3DS marketshares and at the end they would have 2 weaker products instead of a single storng one, doubling marketing and distribution costs.
2nd-Since the Sony brand is much stornger in the HD gaming community, probably Gameboy HD would only recive NGP weaker ports from 3rd parties, no exclusives. While 3DS will only get extremely casual games, since the "hardcore" demand is on GameboyHD, so in this case what's the point of having better graphics (compared to ol DS) and a 3D screen?
3rd-Nintendo has yet to prove they're able to sustain 2 different consoles at the same time and for their entire lifetime whitout droughts, how can they possibly support 3 consoles?
If ever the thing I can expect is a 3DSi version in a couple of years, with bigger screens (not much bigger) and maybe 3G support.
