John Sickels has published his 2013 farm system rankings and the Cubs are 10th. That's 10 spots better than a year ago. The Cubs system has improved quite a bit.
10) Chicago Cubs (20): Another system that has improved quickly. Strengths: hitting at the top: Javier Baez, Albert Almora, Jorge Soler, Dan Vogelbach is a very impressive quartet and there is depth beyond them. Good developments with recent Latin American prospects at the lower levels. Weaknesses: pitching is much, much weaker than the hitting. Improving that has to be a priority.
Of the four mentioned, only Baez is above Low A so the Cubs will have to wait awhile for this group to arrive. It will also be interesting to see how the Cubs go about improving their pitching. They'll take the best player available in the draft when they pick 2nd and my guess is that will be a position player. They'll probably stock up in the next few rounds as they did last summer and hope some of them stick.
It's good news that the Cubs are 10th, but there wouldn't be good news without bad news. The Cardinals have the best farm system in baseball and another NL Central team, the Pirates, also rank higher than the Cubs at 9th. So even with an improved farm system, the Cubs are still middle of the pack in the division. The Reds aren't far behind either.