I used to just hit Exc key and it would disappear.
Now Command+z won't even undo it.
That makes me have to click on it in the layers pallet and drag it in the trash...
Selecting the Move Tool (V) and hitting the Delete-button might be more convenient than dragging the Layer to the trash-can.
The two 'advantages' of the panel are as follows - 1 the TAT tool allowing within image dragging to adjust values. I assume for users without the ability to grasp the concept the most powerful tool, Curves. I will admit that when it eventually is fast enough to use efficiently, and implemented smoothly, this may be a good addition. 2 - the ability to alter opacity and mode of the adjustment, without exiting the dialog. More of a choice for inexperienced users who think this should be necessary at all.
At the moment these two, relatively minor for advanced users, advantages are outweighed by the many disadvantages by a long chalk.
You don't need to do V and then delete in CS4 - the delete key just deletes layers
Who is designing this stuff?