[SpookyZalost]

so modern update 5 years later here's what it comes down to.

SSD if you want speed and high performance at the cost of HDD life (yes SSD 's actually have a limited albeit still very high number of read/write cycles, blame flash media).
HDD if you want decent/standard performance and speed with a longer HDD life and usually much much larger storage space.
Hybrid HDD, this is sort of an amalgam of the first two, a portion of the drive is SSD and that's used as basically a massive cache while the rest is HDD for raw storage.

personally I use SSD's for my OS's and a 2TB hdd for storage, it works well and is very responsive.