bluemoose,
i had the same results, my standard pale ale recipe that clocks in around 4.5% abv came in right around 8%abv. i did not taste the maple in mine but it sure gave it some more body. i too will be repeating this next year!
i have cascade mt.hood, newport, galena, sterling and columbus currently growing. they all seem to so far be doing alright. most are first year but the second year sterling and cascade are doing well.
i did not use juice, but i did do an all grain pale with 100% fresh maple sap. overshot my gravity by a touch. plan on spiken it with some syrup after it has been carbed an cooled.