"no moving parts" - it would be kind of nice to have a hard drive with no moving parts...
Check out this Direct2Dell blog post about solid state drives in notebook computers.
Also, check out some of the performance stats from the press release:
"The new drives can also increase system performance by up to 23 percent5 and decreases boot time by up to 34 percent compared to traditional HDDs available with the Latitude D420 and D620 ATG6."