Actually it's not a service that allows you to watch illegal movies, and neither was Megaupload. It's a cloud storage/file locker service. Most certainly you can use it to store illegal movie files but that's no different to Drop Box, Google Drive and the other similar services.
However, as Kim Dotcom has already pissed off Hollywood, and is fighting them at almost every turn it seems so still pissing them off, I fully expect his new service to be a major target.
But the studios have already been making noises about the likes of Drop Box and Google Drive, saying they too can be used for piracy (which of course, is true they can be) and at some stage I expect them to become targets too.
Mega Upload was used by users to store an awful lot of pirated files, that's certainly true, but when it was taken down the studios and their agents made absolutely no distinction and a huge amount of perfectly legal files were lost too. They've done the same with website seizures, instead of taking down the websites that were hosting illegal files they've usually taken down an entire domain taking offline perfectly legal websites hosted on the same servers. And then they wonder why it's also annoying legal webmasters too.