Long overdue for a good description of this ability:
When I first picked it up, I assumed it was the next advance on base monk speed - it wasn't exactly this, but it's close. Using the ability will instantly teleport you a fixed distance forward, or as far as it takes you to hit an obstacle or an incline of any grade. An important thing to note is that using this will break invis.
In general, it makes for a useful pulling tool, especially against mobs that are unusually fast or snare. As mentioned earlier, the distance you travel is limited only by the terrain in front of you and the limitations of the ability - you'll travel just as far even if snared or rooted.
A second item of interest is that when blinking forward would cause you to decend any distance on the z-axis, you will find yourself on the lowest level where there is ground. In the most basic of terms, if you're swimming, floating or standing on the edge of a cliff when you blink, you'll instantly move to whatever ground is in front of you. While this isn't any kind of benefit while levatating, it can effectively eliminate any risk of receiving any falling damage whatsoever, including the 200k falling damage bug.
End result - it has useful applications (moving while snared/rooted, rapidly moving down z-levels, and closing/lengthening the gap between casters/mobs), but you're not missing much if you don't have it.
Edited, Jul 26th 2009 3:38pm by Shorril