I think the new system oversimplifies for no reason. It doesn't make sense to redo any part of the game unless it makes the game better. The alignment excerpt summarizes each new alignment with a pair of adjectives:
LG-civilization and order
G-freedom and kindness
E-tyranny and hatred
CE-entropy and destruction
[Unaligned=benign, no alignment]
The previous system could have been summarized using the same adjectives:
LG-civilization
NG-kindness
CG-freedom
LN-order
CN-entropy
LE-tyranny
NE-hatred
CE-destruction
[N-balance]
Other than favoring grouping over splitting, the only real change is the replacement of neutral alignment with unaligned.
For me, alignment is mostly a descriptor and I've always minimized the mechanical effects of alignment. Fourth edition makes the mechanical effects smaller than ever before, if not non-existent. That's good. But for a system that's mostly a stereotypical shorthand for describing the ethics of each character, it is no better and arguably worse because it's less specific.
What I wish they had done was present three basic approaches to alignment:
1. Strict alignment--everyone has an alignment. Preferred for beginning groups learning the game.
2. Selective alignment--most characters are unaligned, but certain characters and enemies (clerics, paladins, evil priests, angels, gods, devils, demons) follow a specific alignment. Unaligned characters can select an alignment as roleplaying shorthand, but are not required to strictly follow that alignment. This is for a more experienced group playing a game where the good vs. evil struggle is still a major component.
3. No alignment--everyone is unaligned, and characters act according to individual personalities and complex moral and ethical considerations. Recommended only for experienced groups that agree that they prefer this style of play.
Then, lay out a number of alignment systems:
1. Simplified: good vs. evil, with neutral for uncommitted or conflicted characters.
2. Simplified: law vs. chaos, with neutral for those favoring balance.
3. Classic: two-dimensional 9-alignment system. This is the default for official tournament play.
4. Factional: characters identify with particular groups in the game, which vary depending upon the details of each campaign.
Then lay out the options for any mechanical effects of alignment for each of these basic options, if any, and end by stressing that the DM has final say and any system that is amenable to the group is possible.