This ruling has left open a big question of how much you need to spend to support scrapers and where the line between scraping and a DoS attack lies - and that's going to be a weird line. If my site is producing a big report off of data that changes quarterly then re-downloading that report every 20 minutes is possibly excessive and might wander into the realm of an attack - while if we looked at the same frequency with twitter it seems a lot more reasonable - maybe even a bit on the slow side.