it's always easy to say by consumers' demand. but it's not easy to bring in quickly. it's depends on manufacture supply. we can't also ignore the price point. Apple should wait for price drop. now 32GB or whatever higher capacity is very expensive. if you want it now, you probably pay more than $399.
for example, 64GB SSD for macbook air which is exaclty the same use in ipod flash model is about $1000. can you afford it now?