For the Blue Card, you can change employers as much as you want because it's attached to the employee rather than the employer. Further, depending on the country, after two or three years, you can then legally take work in any other EEA country (except the UK, Ireland and Denmark, all of whom opted out of the Blue Card program). There are some technicalities involved, but those are the basics.
Germany's program is particularly great because you can get a permanent residency permit after only two years if you learn German (to a B2 level, I think), or after three years if you don't speak German. In other words, it's a permanent entry into the EU. I'm an American living in France and I'm married to a French woman, so I don't have to worry, but otherwise, I'd apply for the Blue Card in a heartbeat!
Interesting. I guess Blue Card is not for freelancers, right? i.e. to just directly apply on my own.
Another scenario - I'm a contractor/freelancer working for some non-EU company, but just want to live some period in EU, without changing a job. (Reasons could be e.g. a better school for children, etc..)
It's not for freelancers, no. You can go to Germany and stay up there for up to six months while looking for work, but to get a Blue Card, you have to have a contract with an annual salary attached to it. Your Blue Card is good for the length of the contract plus three months. However, as mentioned, if you stay long enough, you can apply for permanent German residency.
Keep in mind that the German government has been tweaking the Blue Card law, so you probably want to reverify what I've said if you go that route. That being said, I just received a PM on Reddit from someone who moved to Germany after seeing a post I made about the Blue Card and they just got a job offer. They're going to sign and apply for their Blue Card with that contract.
Is the Blue card valid for all of Europe or only Germany? If a german company gives me a blue card can i apply for a job in france or will the french company have to apply for the blue card too? What i am trying to understand is if it is like the H1B visa.
For the Blue Card, you can change employers as much as you want because it's attached to the employee rather than the employer. Further, depending on the country, after two or three years, you can then legally take work in any other EEA country (except the UK, Ireland and Denmark, all of whom opted out of the Blue Card program). There are some technicalities involved, but those are the basics.
Germany's program is particularly great because you can get a permanent residency permit after only two years if you learn German (to a B2 level, I think), or after three years if you don't speak German. In other words, it's a permanent entry into the EU. I'm an American living in France and I'm married to a French woman, so I don't have to worry, but otherwise, I'd apply for the Blue Card in a heartbeat!