I am using KDE 4 trunk. I see options in system settings->Desktop->Screen Edges to "Maximize windows by dragging them to the top of the screen" and "Tile windows by dragging them to the side of the screen". However, both of these are grayed out and I can't seem to change that. Is there a way to enable these options, or are they just not ready yet?

They have not been implemented, I kept them there as a reminder. As hard freeze is less than a week away there is just no time to implement them so they are going to be removed from the GUI.

Darn, that's too bad. I was really hoping for this feature. Well, at least it is in the works so that is good.

Ditto! Prolly the only thing about win7 that I thought useful in today's world with ever bigger monitors. Let's have it!

Isn't it easier to just click the maximize button rather than dragging a window? Or set Kwin to accept double click on the title bar to maximize?

It is very useful if you are already in the process of moving a window, such as between two monitors. Also, tiling windows is much harder than maximizing without this.