After months of betas and rumors, Apple released iOS 7.1 to the public today. The update features a number of improvements, and apparently it also includes support for two new, unannounced tablet models: the iPad4,3 and the iPad 4,6.
Before you get too excited though, the consensus is that these new models likely represent minor hardware revisions for existing iPads, rather than all-new products. It seems the model numbers aren't very far off from current iPad models...