When good opportunities arise, smart managers act. Western Digital (NYSE: WDC) chief executive John Coyne is no dummy.

Earlier today, his company announced a $4.3 billion acquisition of Hitachi's (NYSE: HIT) data storage business unit. Coyne will remain CEO of the combined company while Hitachi's Steve Milligan assumes the role of president.

In a statement, Coyne ticked off all the usual platitudes for a deal like this. Enhanced R&D and innovation. Expansion of the product portfolio. Comprehensive market coverage. Skilled workforces combining.

You know what? It's hogwash. Every bit of it.

The only thing in Coyne's statement that's worth paying attention to is this: "[The deal will] enhance our cost structure and ability to compete in a dynamic marketplace." [Emphasis added.]

He's referring to a tablet-fueled transition to solid-state drives that favors SanDisk (Nasdaq: SNDK) and STEC (Nasdaq: STEC) more than Hitachi, Western Digital, or rival Seagate Technology (Nasdaq: STX). PC demand has slowed as a result.

But don't take my word for it. Earlier this month, analysts at JPMorgan lowered their forecast for hard drive demand. They expect PC demand to grow just 7% this year versus an earlier forecast of 9.5% growth, Barron's reports.

The good news? Large-scale drives are becoming more popular. JPMorgan says that demand for "enterprise" drives for storage of networked data should rise 12.5% this year versus the 6.6% previously forecast. Hitachi has done well in this niche.

With the entire data storage market getting tougher, cost per megabyte has become an increasingly crucial measure for the industry's top dogs. Western Digital has shown it's willing to spend $4.3 billion to win the race to the bottom. Expect its peers to answer the challenge.

Do you agree? Disagree? Let us know what you think about this deal, the hard drive market, and the long-term opportunity for solid-state drives using the comments box below.

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