GMC, Ford, Isuzu, Hino etc. all have 2007 trucks available now, but they are still using the 06 engines.
I would still consider buying one of these.
Freightliner has fields full of 2006 trucks so that is why they are waiting to bring the 2007's out. Same for Mack, Volvo and the other biggies. They all geared up for a big run on 2006 models, but it appears that sales have lagged due to oil prices jitters and weak economic growth over the past quarter.