Tibco RV in a box - would appliances help streaming SQL?

Several others have posted on the new Tibco Messaging Appliance - apparently it's Tibco Rendezvous (RV) in a box OEM'd from Solace Systems. Paul Vincent ponders at the Tibco CEP blog:

It’s quite feasible that the same approach could be used for “basic” complex event processing operations, especially those that don’t require history (or much persistence)

Paul is certainly right that CEP and event/data stream processing engines could benefit from the appliance approach. However I think that it is precisely those applications that require history that could most benefit. A high-speed streaming engine with a co-located database (running with much of the data in cache) gives the perfect environment for answering a wider range of "right-time" BI requirements; the engine can control exactly what needs to be retained and for how long to provide the appropriate time-series data to support whatever aggregated outputs are desired. The database acts as a memory extender (allowing infrequently accessed data to be paged out), as a source of replay / recovery data, and as a history for newly defined streaming queries. The latter is most important - if you want a 1 hour moving average, most streaming queries won't give you the right answer until the end of the first hour.