My 2 cents, I feel many traditional suppliers of PDA / Phone accessories have reservations about offering accessories/ Cases for the Note 2. But myself, as a longtime iPhone user (age 57) just now making the switch to Android with the Note 2, After an underwhelming iPhone 5 release. I know I'm part of a massive baby boomer tech market segment who is just discovering this "Phablet form factor".
Also the Note 2 is having a well financed product launch I'm seeing more online ads for the Note 2 most web sites I go( although that may just be a function of google ad metrics). Regardless, I believe the Note 2 will sell like hot cakes to the segment of aging techies with typical aging vision. Nothing about the experience falls under ther the classification of fashion statement, it's all about remaining competitive and relevant, and finding the tools that will help enable that goal.
If a mass write in campaign occurs, I would think Seidio would change their mind about Note 2 cases.