Drag & Drop Category/Forum sorting

is it too hard to click a button a few time?

that AJAX stuff, while cool, just adds bloat.

I think it should not have to be submitted, for the plain reason that if i dragged it i would never think of pressing submit

I did a page on a website som time ago where the users changed some settings and as I did a post-back on each change anyway I didn't make a submit button. Sure enough, the users came back complaining about the lack of a save button. I wrote a small notice on the page explaing that there was no save button and everything would be saved anyway. No luck, people still complained so I ended up adding a button without any function whatsoever...

lol, but... this is for admins and i think people are more likely to forget to press submit than to be confused by there being no submit

I need your opinion on this:

I am working on a mix between the toolman functions, some xajax and of course the category/forum admin.
Now I ran in to the following issue:

When I allow to move all elements freely then this can happen:
User drags the first category somewhere down and leaves the forums of this category on top.
Now, if xajax immediately saves this state then we have orphaned forums. This is illegal I think.
So, while moving categories without their forums across can be good if you want to assign other forums to it but it can not be a valid state.
This means I will have to introduce a submit button.

The other option:
I group the categories with their forums and only allow to move the forums inside their categories, and the categories as a whole, including their forums, between each other.
This way it would be assured that we always have a valid state and we could use xajax - but it would disable the possibility to move forums to other categories.

So, which one do you think makes more sense?
Or does anybody have a really clever ideas how to solve this?