Angular 2 is still barely out of beta and Google are already talking about Angular 3 with mention of new major versions every 6 months.
However, this doesn't mean you should start panicking and give up on Angular altogether!
Angular 2 was a complete re-write of the AngularJS framework many of us loved for years, whereas Angular 3 is a new version in the same way that AngularJS had 1.x releases frequently.
Todd Motto gives a great explanation of this in his blog: https://toddmotto.com/please-stop-worrying-about-angular-3
Expected in March, Angular 3 will focus on improved tooling and a reduction in generated code, said Rob Wormald, of the Angular core team and a developer advocate at Google. It will feature a template compiler that provides feedback in an IDE on errors in a template, and it will generate 25 percent less code, thanks to improved compilation and changes in the framework's underlying mechanics.