Though this question was asked a couple years ago, I thought I'd post a link to the Houlihan Lawrence website so that others can see what the current mortgage rates are:
914 715 8339
This does not mean you will always find better rates for loans under $729,750. In my experience, only the 30-year fixed gave better rates under that limit. A 7/1 ARM was the same. Hope that helps.
Zack gave you the correct resource to find the answer specific to your question. The products you seem to be referring to are the new Fannie/Freddie Jumbo Conforming loans. As they are relatively new and therefore untested financial instruments at this point, they are somewhat restrictive in qualifying. Dependent upon your position financially you may be better served with a portfolio lender that isn't subject to Fannie/Freddie guidelines. You shouldn't base your purchase on these programs alone. Full pre-approval is the best way of knowing what program is the best suited for you and can therefore assist you in determining your purchase price. Contact me if you would like more information.