In response to growing consumer discontent with the Jawbone UP, Jawbone has announced a "No Questions Asked" guarantee. As of December 9th, Jawbone will offer a full refund or replacement to any user. No questions asked. Oddly enough, Jawbone is even allowing you to keep your UP but still receive a full refund.
I've been using my Jawbone UP for quite some time now, and have experienced no issues so far. Still, it's good to see the company taking accountability for its problems, and working toward fixing any reported issues.