A few notes:

According to wikipedia, since 2007, Japan has an earthquake alert system in place, broadcasting warnings through TV and radio, etc, nationwide which may have given many people a minute or two to get ready.

Given the proximity of the epicenter to the coast (130 km to the closest point on land according to wikipedia), I really doubt many of the folks on the coast had much time even with the tsunami sirens going off (a system that has been in place since the 1950s). There are certainly video clips with the sirens going off, but I'm afraid in this case, the quake was just too close to the coast for too many people.

Re: our apparent indifference to the tsunami advisory. You have to understand, we have some of the worst local news broadcasts in the world. That is no exaggeration. These are "news" people who think every car chase is worth airtime. Where Lindsay Lohan is more important than local issues (City of Bell, anyone?). Where a barely measurable amount of rain warrants a "storm of the century" headline. So the typical overhyped, ham-fisted approach just means many never listen to the plastic surgery cases who cry wolf.

Plus this is Hollywood. Tsunamis are only waves that tower over skyscrapers, right?

Tsunami prediction is fairly good, and the Pacific is well modeled as to how an earthquake would propagate and who would suffer more. Hence the tsunami warnings for Hawaii and points north of us whereas we were issued the less severe advisory. We do have some local geography (e.g. the Channel Islands) that work in our favor in these kinds of events. I imagine should a similar earthquake occur in the Pacific Northwest, we'd get hit much harder.