The Game of the Year version recently hit a local retailer. What does this version offer vs. other versions?

What level of patches will it include?

It appears to me that Entrenchment is download only. I live in a rural area, no hi-speed internt, so any major downloads are very problematic. Since Entrenchment is a major addition to the game, would it be better for me to wait and see if a combined Sins and Entrenchment are released in one physical copy?

 Thanks for any info.