Chocona Rules

I think this puzzle shows some promise to be an interesting puzzle type.  I like how the logic seems to work more towards "Where can't the black squares go?" rather than "Where can the black squares go?"  It works thusly:

1. Some of the cells must be painted black.  A number in a heavily bordered region indicates how many cells in that region must be painted black.  A region with no number can have any number of black cells, including zero.
2. The black cells must create only rectangular or square areas.
3. The rectangular areas may include cells from different regions, and most likely will.
4. Two different rectangular areas may not touch along edges.  They may touch at corners, though.  (Thanks, Marcin, for pointing out this missing rule.)

Check out the sample below.

You'll note that there is no requirement for all the painted cells in any particular region to be connected.