Susan Moskwa from the Google Webmaster Central team explained it was removed because Google keeps telling webmasters “that they shouldn’t focus on PageRank so much.” They felt it was “silly” to keep telling webmasters that, and at the same time show it in Webmaster Tools. So Google removed it from Webmaster Tools. I think this is a good thing, since I agree it is obsessed over too much, plus what Google showed in Webmaster Tools was not very useful to webmasters.
But I really think Google has to take a stronger stance, if they indeed want webmasters to not obsess over the score. At one point back in 2007, Google asked webmasters about removing PageRank from the Google Toolbar for this exact reason. The conversation and discussion ultimately died with no recourse from Google. I personally would like to see Google remove the PageRank score from the Toolbar as well. Yes, the Toolbar shows page by page PageRank score, but we all know that Google shows out dated PageRank data in the Toolbar, plus it is often buggy.
I think, Google should either make the data accurate or remove it – just like they did in Webmaster Tools.