Actually SGT rock's site had some very good comparisons on
a per-day basis for exactly this type of stuff. Yeah.. have a look Here

My experience tends to hold it out - I am lighter total with alcohol and a good alky stove rig (penny stove) for about 6 person days, doing 2 cups of water in the morning and 2+ in the evening. Above that, a light canister stove (a -la MSR pocket rocket or snow peak) starts to be lighter, depending on the size cartridge you take. So barring other factors I'd say if you're out for 7 or more person days as described above at a time, a canister is lighter. There are of course other factors that might make you do alky on a longer trip - fuel availability, etc. Were I ever to attempt a long thru hike in canada where I were resupplying myself, I would still do alcohol, because I can get it (as heet type stuff) in every gas station in the country. I can't get isopro canisters everywhere.

As you mention as well, it also depends on if you're looking at the max weight carried, or the average over a long trip.

White gas stoves have always been in total too heavy to compete - even though in theory the fuel is more efficient -
haven't checked that out with my 9 oz borde stove yet