rent to own in williamsburg lisitings/advice????

I haven't looked into this but isn't this of little value if the reference purchase price of your call option on the apt is way above realistic price of the apartment (and that is the likely tactic of the seller granting you this). So, what's the point? If you were planning on renting anyway, I suppose you could say it is no harm, but it is very unlikely to be of any benefit, at least that is my guess.

I'd be interested in this as well. Anyone have any suggestions regarding which developments are offering this?

One Northside Piers is offering this.

also decora and jacksonia

Sometimes you can negotiate that if you complete the purchase, a part of the rent will be deemed applied towards the purchase price.

That also may create some liquidity if financing is an issue- a lender may recognize that part of the rent as money down as well, reducing what you have to come up with at closing.

Be careful that any purchase has a financing contingency so that if you elect to purchase and they want a full 10% downpayment at that time, you can later canel if your financing doesn't come through.
Also be careful about hidden provisions concerning the condition of the apartment because sometimes the agreement states that you will accept the apartment at the closing down the road in the same condition it's in now. You may want more protection as a buyer than you would as a renter.