Yes, that's new form. Append is her upgraded version, a rerelease by Crypton. She sounds great, and comes with 6 new expressions Light, Dark, Soft, Solid, Vivid and Sweet.

It'd be nice if they were the same song, but ya know, can't have everything. Anywho, the upgrade allows Miku to sing low notes much better than she used to be able to. Not so sure about her new look though. An 'untrained' ear might not be able to hear the differences, but trust me, there are differences. This probably means that there will be 6x more Miku songs on the Vocaloid rankings. So expect more Miku on the Vocaloid feature!