Hurray for you! I, too, have a successful one-night W/L story...wanted OKW 6/22-6/29 and 6/26 was not available...so I booked all but 6/26 on points, and 6/26 on cash, and W/L'ed 6/26 for points...W/L came thru in less than a week (altho the cash reservation went on my credit card immediately and it may take 2-3 months for the credit to show up...but Disney says they put the credit thru the same day the W/L came through, so my guess is the delay in the credit is the bank/credit card company, not Disney)...
This happened, in almost exactly the same way, last year, too; but for an early May reservation at BWV...
Not a scientific poll by any means, but it seems to me that unless you're looking for a super high-demand time/place (e.g., NYE), one-night W/Ls have a high degree of success...it's the multi-night W/Ls that seem to take more luck...