Personal computers are destined to join the ranks of obsolete technology like cassette tapes and typewriters, an IBM executive has predicted in a blog post.

"I, personally, have moved beyond the PC... My primary computer now is a tablet," writes Mark Dean, chief technology officer at IBM. "When I helped design the PC, I didn’t think I’d live long enough to witness its decline. But, while PCs will continue to be much-used devices, they’re no longer at the leading edge of computing. They’re going the way of the vacuum tube, typewriter, vinyl records, CRT and incandescent light bulbs."

Why the introspection? The 12 August marks the 30th anniversary of the launch of the first IBM Personal Computer, a machine that could be described as the great-grandfather of all modern PCs.

Dean echoes Steve Jobs' sentiments. At the D8 conference in 2010 Jobs described a "post-PC era" by likening PCs and tablets to trucks versus cars.

Desktop sales are falling, and more advanced tablets sees the touchscreen form factor eating into the consumer laptop market too. Dean, however, believes that it's not tablets that have led to the decline in PC sales:

"PCs are being replaced at the center of computing not by another type of device - though there’s plenty of excitement about smart phones and tablets - but by new ideas about the role that computing can play in progress. These days, it’s becoming clear that innovation flourishes best not on devices but in the social spaces between them, where people and ideas meet and interact. It is there that computing can have the most powerful impact on economy, society and people’s lives."

This is not to say that this decline will be immediate, as some stats report that around 400 million PCs will be shipped in 2011, however they are, perhaps, no longer central to our digital lives.

It is clear that as our organic interaction with the world merges with the digital, we'll increasingly need devices that cement that process. Although the onset of mass-scale cloud computing and better hardware will ensure that this happens sooner rather than later, it is important to pause and take stock of where this will take society; often, the speed of technological development creates the illusion that innovation is shaping society rather than the other way round.

What are your thought? Will you still be using a full-on PC in the foreseeable future?