I don't think 1 quart in 1000 miles is acceptable - not by a long shot. This number seems to be the level where a company will consider a rebuild.. more than 1 qt in 1000 miles cannot be passed off as "normal", however bear in mind the manufactuer does NOT want to rebuild your motor so what they call "normal" is not normal for the consumer. I personally believe that if I need to be adding oil between changes at 3000 miles, then I have a problem.
Personally, my '98 GTS doesn't use any oil. I autoX it, drag race it, and commute in it a lot - and I MAYBE lose 1/4th of a quart in 3000 miles - if that... and the Viper holds about 8.5-9 quarts.
Autocrossing or drag racing will often cause your car to use a little more oil, but even then you shouldn't have to add a quart per 1000 miles... If I lost a quart in 3000 miles of HARD driving, I'd be slightly disappointed, but that would be MY limit before I thought there was a problem.