Any new information on this, as I just recently did this as well, and believe that I was dropped from the index due to a Google glitch. Would love to hear from others who were restored to the index and ranked once again.
not all reinclusion requests seem to follow the same process. some reinclusion requests are ignored, others denied and some are approved. of the ones that i have experienced being approved it does not seem to always follow the same path. the end result is always positive.
When the problem is truly just a Google glitch, often (but not always) the fix is fast - within a few days to a week.
However, I know of one case where Google denied it was their glitch, and yet after 3-4 months the rankings were fully restored. Unfortunately, this was after a lot of staff at the business involved lost their jobs ;(
My theory in that one case, and it's only a theory, is that the glitch was in one of their internal manual tools. The original reviewer who caused the penalty didn't question the "false positive" and the WMT reviewer fell into the same trap. Later, through who knows what kind of discovery, something was fixed and rankings returned.
At that same time, I also heard second hand of a few other sites who were wiped out in a somewhat similar fashion. In those cases, they rebounded within two weeks of their reconsideration request.
So, as goodroi said, general rules are not easy to come by for the complex system that Google has now constructed,