That's a tough one, and a very personal preference. Yes, I think it will be similar to BLT, and the minimum buy-in will be either 100 or 160 unless Dis decides to change it. That's been pretty standard over the last few years.
Here are some things to consider:
1)
Will you go regularly - Is traveling to Hawaii semi-regularly realistic? Not sure where you live, but for us (family or 4 in OH), we couldn't afford to fly there regularly. We can hop in the car and drive to WDW or VB in 15 - 17 hours. Flights for us to Orlando are also much cheaper than Hawaii as well.
2)
Buy in Price - VB is selling for $55 - $60 per point. By the time Hawaii is build, I'm guessing it will be $115 - $120 per point.
3)
Timing - When will Hawaii actually open? There are rumors that Disney is postponing the ground breaking until the econmy bounces back. Not sure that's true, though.
4)
Maintenance Fees - Both will be high. It's an ocean front property.
5)
Contract term - Hawaii will expire 2062ish, while VB will expire in 2042. Are the extra years important to you?
6)
Resale value - I would assume Hawaii would hold a higher resale value than VB because of location and contract term.
7)
Point Structure - You probably won't go to Hawaii for 5 days. So, even if you can buy in for 50 points, will 150 every 3 years be enough the get you the reservation you need? Not sure.
For us, as much as I'd love to go to Hawaii, I can't see us using it often. If I can get a couple or three trades over our lifetime, that's wonderful. We'll use VB much more. I like having the 11 month booking window at VB, and for $60 per point (what I paid earlier in the year for my contract), I don't feel bad using those points in WDW on occasion. However, if your plans are to use the points in WDW, buy a WDW resort. You can buy in much cheaper at most resorts, have lower maintenance fees over the life of the contract, have an 11 month booking window on property, and still use them for Hawaii. The first couple of years may be tough to get a reservation, but after that, the resort seems big enough that it will have availability at the 7 month window.
Best of luck deciding!

I don't have enough patience to wait till Hawaii is built!
