On June 10th Apple revealed iOS 7 in all its redesigned glory and, at the same time released beta 1 to the developers. This has since been followed by the 2nd and 3rd betas. Much debate surrounds the subject of downloading iOS 7 via the IPSW. There are 2 ways of doing it; one is down the official Apple route (Dev Centre) and the other is via pir@ted links.
Sharing any pirated links is illegal, no matter what they are. And, downloading from these links is a dangerous practice. Unofficial links may contain viruses, malware that can destroy your device or that have the ability to steal your personal data. Another reason why it is dangerous is this – beta versions are for testing purposes only. They are unstable, may not be totally secure and are full of bugs and issues that need resolving. This is why Apple only allows official developers access to their beta firmware.
Official developers will receive support and backup from Apple should there be any serious issues. They also have each other for support. Unofficial downloads are not supported in any way and you are taking a huge risk that you are not going to destroy your expensive iOS device. Also, bear in mind that most developers do not use their main device to download betas onto; they have a spare or two just for this purpose.
If you want to get your hands on the iOS 7 IPSW, you should register to become an official developer. It costs just $99 per year which is a small price to pay to be able to get access to the iOS 7 IPSW legally.
Recently, Apple requested that their employees do not download the beta iOS 7 IPSW either. They have warned that any employee caught with the download unofficially faces disciplinary action.
At the end of the day, illegal or not, pirated links do not harm Apple in any way since they can only be downloaded onto iOS devices. And, it would appear that they are also allowing quite a few activations without UDID numbers so it seems that they are keeping things pretty open at their end.