My Optimus G Pro review (of the Korean version) will be on the way later today, but it sounds like LG has finalized plans to bring its Note II competitor to the US, a la a follow-up to event it announced last week, scheduled for May 1st.
LG sent out official invitations to said event today, and they're not even trying to hide the star of the show: the Optimus G Pro is on its way to America. While the invitation does not announce any specific carrier partnerships, Sprint and AT&T both carried the Optimus G, so they're probably the best starting points.
Last year, LG did not actually announce carrier partners at its US launch event for the Optimus G, so we're not sure what to expect on May 1st. Perhaps LG will wait for CTIA to reveal just who will be selling the G Pro on this side of the Pacific, but I guess we'll just have to wait and see.