The 7mm market is still in its infancy. When you put it on a timeline the 7mm category is actually newer than solid state drives. The underlying technology behind these 7mm drives is tried and true, a traditional HDD in its simplest form. Hitachi has hit the ground running and isn't standing still with just one offering in this new category, which is good for consumers looking for a way to speed up their netbooks.
With that said, Netbook users aren't the only ones to benefit from the new 7mm form factor. The drives are being sold at very low prices so anyone with a need for more storage at a low cost can get in the action as well. Looking back, I wish I would have taken a closer look at Seagate's Momentus Thin when I had the opportunity so I would have performance data on hand for this article.
As it sits now, Hitachi is the one company offering a 7mm drive that is larger than 250GB. If you are more worried about performance rather than capacity, Hitachi is also the only company offering a 7,200 RPM 7mm drive as well and it also can be purchased with 320GB of storage capacity.