I would also guess it's the OGL sheet. I personally prefer the Shaped sheet because it has more functionality and awesome support for monster and spell import via the companion script, but both of them are alright to use. The comparison between them comes down to, essentially, aesthetic sensibilities, and a certain tradeoff of features vs snappiness. As Ed said, just try them out. It also seems some people like the Community sheet, for reasons I cannot understand if you value your time at all*. Perhaps it's mostly inertia. *To expand this: the Community sheet has no form of automated import, not even compendium drag & drop, for monsters or spells. So if you like data entry, this is the sheet for you. ESPECIALLY as the GM. Otherwise, not so much.