The original Playstation came out in 1994 and wasn't discontinued until 2009. The PS2 is still being manufactured. PS3 still has a while to go by that metric. If you want to talk time between models, PS1-to-PS2 was 6 years, and PS2-PS3 was 6 years, leaving PS4 to be only slightly behind the curve if it comes out next year.
Consoles have always been subpar in some way or another compared to top-of-the-line PCs at release; that article's claim is silly. My PC at the release of the PS3 had four times the PS3's RAM, and it wasn't even top-of-the-line. One of the biggest benefits of targeting a console is that it's a stable, homogeneous platform.
Tablets and phones aren't the new consoles, they're the new GameBoys. In that way, I agree with you that they could hurt Nintendo the most, mainly by virtue of the DS having been the leader in that market.