Pace of innovation

If we accept the claim that Apple's (or a lot of other companies) innovation is to take an existing solution which is available on the market and reinvent it, we can set up this table.

Invention	Year	Original	Year	Difference_(years)
Apple II	_1977_	IBM_360	1964_	13
Macintosh	1984	Workstation_(Xerox_Star)	1981	3
Newton	1993	Psion Organiser	1984	9
iPod	2001	Sony Walkman	1978	23
iPhone	2007	PDA (Newton)	1992	15
iPad	2010	Tablet_Computer_(EO)	1993	17
Apple TV	2012	Set top box (WebTV)	1996	16

Naturally one rightly can argue that this sample is statistically not relevant and it's not clear what should be considered as an original invention. I still see a pattern there; apparently it takes 10-20 years to reinvent a technical innovation.

If this is the case what can we expect? What has been invented 10 - 20 years ago? Should the Web (WWW) reinvented? The iPod or the Mac? Probably the DVD (but it's only a larger CD)? Segway? Search? Social networking? Digital photography?