Rejoice, oh Android lovers. Thy OS of choice has finally graduated to the point where its latest variant is also the most used -- a statistic that is likely to last for only a day given Google's intent to reveal Android 2.2, or Froyo, at its I/O conference tomorrow. For the first time since El Goog's been keeping these platform version stats, 2.1 has risen above 1.5, the previous incumbent, having grown from 32.4 percent on May 3 (chart after the break) to 37.2 percent on May 17. This rapid ascension can only be expected to accelerate with