Yes, FemShep accounts for about 20% of playthroughs despite being 300% better.
I don't think ME3 was really a surprise, to be honest. The guy who did the voice on that trailer sounded a bit like a younger Robin Sachs (Zaeed Massani in ME2, Carth's captain guy in KotOR and Harrowmont/Seneschal Whatshisface in Dragon Age, for those who don't know who I mean), but it could just be the London accent talking.
I'm not a huge fan of Earth being the target, but in a way I can see why they've done it. Youmanity (Sorry, can't stand The Illusive Man) is, thanks to Shep, the biggest threat to the Reapers and their plans. What better than to target the home of Youmanity and perhaps even weaken Shep's resolve? It could be a psychological move rather than a tactical one, intended to instill fear and despair rather than weaken their defenses.