Pros / Cons for JavaScript API?

Discussion created by danielkse on Jan 3, 2013
Latest reply on Jan 10, 2013 by TruthOf42
I have searched for some sort of list with pros and cons for JavaScript API against the other API's but  haven't found any so can you with experience please help me with this?

What is good with JavaScript API?

What is not so good with JavaScript API?

Is all API's developed at the same time?
Does JavaScript API have the best performance?
Any limits on the JavaScript that other API's doesn't have?