One thing you'll notice if you look at this on Google Maps yourself is that the area is huge, and actually pretty easy to spot. I'm serious, go see for yourself. Unlike those stories where Google Earth was used to find ancient Roman villas or undisturbed forests, and involved someone with multiple Ph.D.s sitting hunched over a computer for days on end, this "Atlantis" can easily be spotted by a half wit with four or five beers in him (That's a pretty fair description of most English, actually).
The fact that it's so easy to spot suggests to me that it might not be terribly unique. In fact, after a couple minutes of scrolling around the world, I've found similar straight line/right angle combinations off the coast of Ireland, in Hudson's Bay and a little northeast of Siberia. Which means that the Atlantians were either prolific road builders and I just became the world's most incredible oceanographer, or that I have found absolutely nothing, and remain the idiot that genetics and past history say I am and always shall be.
So what to make of these lines then? Well, in the original Telegraph article, the reporter managed to get a quote from an Atlantis expert, but didn't bother talking too an actual oceanographer, or you know, Google. In fact, when someone did eventually get around to calling them, a Google spokesperson squashed the story. They stated,
"Bathymetric (or seafloor terrain) data is often collected from boats using sonar to take measurements of the seafloor. The lines reflect the path of the boat as it gathers the data."
Which sounds relatively convincing, in the same way that it sort of made sense when Geordi LeForge inverted the polarity of the subspace wheezit to get the Enterprise out of another inadvertent-holodeck-sentience related jam. As a web comedian, I'm marginally underqualified to analyze the scientific merits of Google's explanation. What I am qualified to do though is express disappointment that Google didn't try and string this along for awhile, and see how this played out. You know, act all mysterious for a couple months, or at least until a few lunatics drown in the Atlantic in homemade diving rigs. By clarifying this issue so rapidly, Google may have been acting in an ethically and scientifically responsible manner, but they really shit in the cornflakes of a good potential prank on conspiracy nuts.
Here then is how I would have strung along the world for a few days, provided I was in some sort of position of authority at Google. Senior VP of Jerking Around The Rubes perhaps.
1) Quickly replace this section of the map with a version that's digitally manipulated to reveal no grid like lines. Deny the published images are real. Blame it on overactive imaginations and Photoshop trickery.
2) Adjust the search results for "Atlantis" to prefer sources that downplay any historical basis for Atlantis. Edit Wikipedia liberally with the same intention, leaving Google IP addresses in the logs.
3) Change every font on Google to unreadable and ancient looking glyphs for a few hours. Nautical themed if possible. Seaweed and tridents and whatnot.
4) Quietly funnel billions of dollars into research on artificial gills. When this information leaks, issue a public statement denying the allegations. Be sure to unnecessarily confirm your allegiance to the "dirtwalking government of the United States."
5) Find an old bomb siren and install it on the roof of Google HQ. Set it off one day, and have everyone rush outside to the front lawn in a panic and start building an Ark.
6) For the suspect region, at the maximum zoom level, replace the "we don't have imagery at this zoom level" error message with this: