The question still stands: can HBO become Netflix faster than Netflix becomes HBO. Both are in an arms race to buck up the aspects they're weak on. Netflix has ramped up quite fast with its own original programming. However, this move by HBO is a strong move. At $14.99/month it should attract a good bit of cord-cutters and cord-nevers.
Also a very smooth move by Apple to secure exclusive rights to host the HBO Now app for the first 3 months. Very savvy way to push product for Apple (and no coincidence that they lowered the Apple TV price to $69 USD).
UPDATE (3/15): For additional discussion surrounding HBO Now check out the March 11th episode of the always insightful KCRW podcast The Spin-off.