At this point, touting any horror movie as 'based on a true story' or 'inspired by true events' or however you phrase it serves to me as an indication that "we didn't think this was scary enough, but we want the gulliable teens to buy tickets" -- a marketing tactic which occasionally backfires (my younger brother knocked the plausibility of The Strangers on this count, but if they DIDN'T say it... would it have been a scarier film? How about a successful one?).
Regardless, The Haunting in Connecticut -- starring Virginia Madsen, Martin Donovan and Elias Koteas -- appears to be following in those footsteps, with first a poster and then a trailer purporting that this tale of a family tormented in their new home with a mysterious past is at least fact-based(-ish). (Why, yes, you're correct in thinking that they already remade The Amityville Horror.)
Throw in a bunch of loud noises, and you've got yourself a probably PG-13 one-weekend wonder that was shot in 2007, but won't get dumped in theaters by Lionsgate (without press screenings, natch) until 2009. In fact, I'm willing to bet that it'll land somewhere between next Feburary (in the wake of other teen-targeting horror fare of The Unborn -- which actually looks creepy, if familiar -- and The Uninvited and My Bloody Valentine 3D and Friday the 13th) and maybe next April, before hitting DVD just in time for Halloween renters to settle for anything vaguely supernatural on the 'new release' wall.
Or, who knows, it could be good; if it takes proving me wrong to do that, I've eaten feet for less. (True story.)