It's now playing at the Minetta Lane Theatre in NYC. Go see it and tell those of us stuck in Los Angeles what it's like.
From their website:
Walmartopia is an irreverent political satire of big business and eternal smiley faces, a musical tale of a single mom who speaks up to her corporate employer and finds herself and her young daughter jettisoned to a future where Wal-Mart dominates the entire world.

wal-martsux.com