CommandQueue questions

Hi,

Couple of questions reg. the CommandQueue (in same spirit of the ones 
reg. the
Cache):
1/ is it possible to "manage"/"view" a Queue, that is can a Queue be 
queried to
see which commands are running + can running commands be interrupted
(I know this is a though one, but I still need some way of interrupting long
operations, the well-known dough-experience)
2/ can a command send messages to the queue about it's status (e.g. a 
progress
meter for long running commands, providing feedback to the end-user) ?

I have some sort of a solutions for 2/ in my-very-naively-implemented-queue-
which-I-am-trying-to-get-rid-of, be happy to contribute those if someone is
interested/can help me on the right track...

Thanks in advance for any comments,

- Filip