tedster - 7:15 pm on Oct 25, 2011 (gmt 0)
These slightly more informative messages did begin last spring - and in more recent months the variety of messages is said to have increased, although I haven't seen any of the new ones.
"No manual penalty" is a way of saying "we're not changing your site's rankings because of your reconsideration request." In other words, the algorithm itself gives you your rankings, no factor or action was added manually.
That begs the question a bit, because there are definitely anti-spam elements in the algorithm. The point is, I assume, that if you fix or change those factors the algorithm will increase your rankings automatically and you don't need to file a reconsideration request to make it happen.
In other words, and Matt Cutts has confirmed this, a reconsideration request is only going to have a beneficial result if there was a manual penalty. However, only some manual penalties are lifted immediately after a successful request. For others, the penalty will have a time-release effect, even after the "infraction" is repaired and you submit a reconsideration request.
I do appreciate Google's efforts at more clarity in their webmaster communications, but making complete sense of any particular situation is can still be like trying to solve a Zen koan - and I'm still no good at clapping with just one hand.