I recently purchased the Grandmaster Edition and I am working my way through some of the instructional materials.  I say "working" but it is much more enjoyable than that sounds.  Overall, I am very impressed with the quality of this product and would recommend it to anyone at or below my current level (mid-1500's).   

I have CM 10th edition and I started my first somewhat serious chess steps from there. It has great tutorials and if you finish them successfully your understanding of the game will be increased a lot. And I myself never seem to find the time to go through them thoroughly. Highly recommended...

Hmmm....

Captain Obvious here.

Rook16 is evidently impatient with newbies like me who are just picking up the chess bug.  Clearly my post on Chessmaster was not intended for Rook16 and the other illuminati who have dedicated their lives to the game.  I am humbled that he even bothered to mock my pitiable effort. 

Humbled and awed.  What a classy guy, eh?

This is Captain Obvious, signing off.

Live long and prosper.

Neil

I've used Chessmaster off and on since CM 2100 in the late 1980s. Although I much prefer Fritz and Chessbase (Hiarcs is my preferred engine, 'though I'm gonna get Rybka 4), I still use Chessmaster.

One use I find for the beast is playing rated training matches under tournament conditions. The personalities (I'm in the midst of a match with Dave) do not play like humans, but the errors they make are few, and the beast will punish blunders. It can be useful training when combined with other methods.

I've done some comparisons of Chessmaster's analysis to that of Fritz: http://chessskill.blogspot.com/2009/12/chessmaster-versus-fritz-analysis.html