I couldn't agree more. Art (by its very nature) evolves along with society. Page's guitar work is masterful, no doubt. But music has evolved, and part of that evolution includes the advent of the synthesizer as a legitimate musical instrument. It has its place, every bit as much as the trumpet, piano or guitar. Just as with all instruments - the beauty of the sound is directly proportunate to the skill of the musician. You can have very good synthesizer or you can have crappy synthesizer.
To limit Led Zeppelin exculsively to Page's guitar (or to limit ANY group by abstaining from certain instruments) is to limit that group artistically; to limit its creativity.
That said, this is a decent & fresh "re-invention" of the rock 'n roll legend that is Led Zeppelin. It's extremely GOOD, but it's not predictible. It doesn't not sound like "everything else" that was done by Led Zeppeln. And who would want it to? To reiterate; "In Through The Outdoor" is fresh and new, but at the same time, it's got that Zeppelin edge that gets your feet start tapping.