SCE-MI 2.0 should support
time consuming exported tasks.  These
would be very useful in a model where the BFM on the HDL side presents time
consuming tasks to execute its transactions. 
The C side would call an appropriate task to execute a given
transaction.  This becomes a quite
natural way of seeing the HDL as an extension of C.  The call blocks on the C side until the
transaction has completed and C gets a status code back or in case of read
transactions it gets the read data back.