Hmmm..... I'm not really quite sure how to digest this one.
Seagate is a good drive, although there have been some stumbles in recent years (7200.11 model 1.5TB drive fiasco in 2008, for example).
And then Samsung goes both ways, neither a normally-suggested disk, nor necessarily a bad disk.
Seagate finally phased out that crappy brand 'Maxtor' after that merger some years ago (2006). Many people mistakenly think Maxtor bought out Seagate (again, thanks to the 2008 drive disasters) and made Seagate "bad", but it was Seagate that had the majority stake and control.
From what I can read, these are all related to technology acquisitions. It's actually cheaper to buy out a whole company, rather than pay them rent/royalties to use their patents.
Last month, Western Digital bought the Hitachi GST hard drive business: http://news.cnet.com/8301-1001_3-20040001-92.html
That's a wash there, too -- both are good companies.
In the above Seagate article, notice it mentions Toshiba -- a company that dropped out of the optical HD race (HD-DVD) in order to focus on solid state media. I'm betting it is the next one to fall. That, of course, would create a duopoly, and allow for a third party to emerge as new competition. I can see that happening.
I'm actually surprised Ritek/Ridata has never gotten into the spinning drive business. They're all over the optical and solid-state (Flash memory) world.