The official line is:
The foundation of the G1000 has all of Laminars underlying code in it. All the radios, airways, map drawing, etc... is stock G1000. Saso, the person who coded all the systems, simply added more features to it and customized it to reflect, on the surface, a TBM900 G1000. So, if there is a problem with the fuel estimates, due to the fact we are using Laminars fuel code, you will need to file a report with them so they can address it.
For the record, this has been addressed already in several other forum posts. So we haven't ignored this topic.