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.