Folks, what are your experiences, positive or negative, of using OKRs (Objectives & Key Results)? These originally stem from "Management By Objectives (MBO)" but have gained traction through their use by Intel, Google, Twitter, etc.

Correct me if I'm wrong, but the key differences between OKRs and standard objective-setting seem to be:

1. Demarcation: Separating the aspirational goal (Objective) from multiple, measurable, timebound steps (Key Results)

2. Transparency: Everyone can see everyone else's OKRs, up to senior management, in order to aid alignment

3. Agility: OKRs are often reviewed monthly, rather than traditional mid-year/end-of-year objectives

The people who use OKRs tend to advocate for them really passionately, however I'm wondering if standard objective-setting can work just as well, and whether there are any drawbacks to the points listed above?