I like the categories and descriptors. They definitely look useful.
On Two-Weapon Fighting: Granting extra attacks due to wielding multiple weapons doesn't fit well into the 4E system. Most character attacks will use powers, and each power has a description what kind of action it requires to use. How do you handle this with making multiple attacks? Either you can only use a power and ignore the off-hand attack, or you grant the benefits twice, which obviously leads to overpowered effects. Neither is satisfying.
So, if you want to fight with two-weapons, all the time, you'll need a power for it. I wonder if it will be a at-will attack power for the Ranger (I don't know if that would be balanced), but I think most of the time, you'll use your encounter powers to gain extra attacks. To compensate, you won't suffer any penalties.
A general tendency for 4E seems to be to eliminate direct penalties. You don't get a non-proficiency penalty, but a proficiency bonus. When you perform a special maneuver (via a power), you don't suffer penalty or bonuses, but you get to deal damage and a special effect. To compensate, you can't do it at-will.
It's only consistent to do the same for two-weapon fighting.
People might still disagree with this basic design assumptions, but that's what they are, and I think it is a wise choice not to break with them without a real need.
I hope as much as anyone else that it will be easy to add additional two-weapon fighting powers to other characters, but I can live without it. If two-weapon fighting is my character shtick, why _not_ play a Ranger?