Yes, they are completely different. But before you start building a real application / project, I recommend to you to wait a little bit until it is officially released. You can start learning but make sure to check the changes between the Release Candidate versions and the official version.
There is significant enough differences, given that Angular2 is a rethink and rewrite, that support the idea that if you're just starting out you're not hindered by the "That's not how we did it before" thinking that coming from Angular1 will raise for many. An advantage as such... of course many developers are used to wiping the slate clean and ramping-up again with a new product version, in which case experience is an advantage.
In short, I've not seen any compelling enough evidence to suggest that if you are starting out Angular1 should be chosen over Angular2. While it's still in RC it's a good time to get ahead of the crowd also.
Fakiolas Marios
Full-stack JavaScript lover, happy husband, proud father 😉 - Head of Web & Frontend at @omilialtd
Yes, there is no need to deal with AngularJS 1.x. Angular 2 is rewritten from the ground and it's not just an upgrade but a totally different framework. Many features have been deprecated and even more were introduced. For sure an experienced AngularJS 1.x developer might make the switch quite easily but you don't have to worry about this. There is a learning curve but this is sth normal since you want to master such a super-useful tool.
For me the key points you have to feel somewhat confident before digging into Angular 2 are:
Keep in mind, Angular 2 is in RC so it is a step behind stable release but not there yet. Surely you can start playing with it since there are tons of educational material out there and a solid community to support your efforts.