Avi, Did you not see the aggregation report by Tony Bates on cidrd posted periodically for the last couple of years? It lists aggregation gains for each origin AS, rather than the BGP neighbor in your numbers. IMHO, numbers based on origin AS is much more useful.
If you need to invent wheels, let us at least invent better wheels :-)
-- Enke
No, I missed the ASnum-based report by Tony on cidrd. In any case, I thought it would be useful to try to gather the data independently on real data in use by our network... Also, the report based on ASN tends to miss JVNC etc... which can be aggregated by their transit provider at the peering/exchange locations. Reports based on just next-hop seem to catch the top-level aggregation possibilities (i.e. a customer of JVNC & a customer of some other ISP might have adjacent /24s that could be aggregated)... Avi