It looks like 2.5-inch 7200RPM HDDs are about to get their first nail in the coffin from Seagate, who has confirmed they will discontinue their faster 7200RPM 2.5-inch drives later this year. RIght now we have four drives in the 7200RPM 2.5-inch lineup, Momentus 7200.4, 7200.2, Momentus Thin 7200 and Momentus XT.
The move shouldn't be a shock with the massive price shifts we're seeing in SSDs, where they're close to $1 per GB now. Not only are they cheaper, but they offer far superior performance to mechanically-driven drives, with less heat and noise which is all better for a notebook. Just because Seagate are moving in this direction, it doesn't mean we'll see them completely dive out of the performance HDD Market, as they'll put more focus into hybrid drives.
As time goes on, we'll most likely see HDDs expand past 4TB and SSDs level out at around 512GB to 1TB at less than $1 per GB. Storage, like all technology, is a constantly changing market and we as consumers all benefit the most.