It can certainly be interesting, but most of the interesting research being done is related to the intersection of languages and security. There do exist formalisations, but they are derivative works based on the GREAT papers.
Notation is for the most part boring. The way you write function literals has no effect on the semantics of the language.
The prototype inheritance is also boring, the small step semantics being two inference rules[1].
JSON-style literals are what. A way of writing a POD. Who cares. It is boring.
Asynchronous execution is also boring. It was novel in the 1960s, it is not novel now.
There is interesting stuff about notation (in my opinion to do with parsing but perhaps thats my bias speaking), but people being "picky" about notation is theoretically dull.
If you're interested, "Programming Language Syntax and Semantics" by D. A. Watt, and "Syntax of Programming Languages: Theory and Practice" by R. C. Backhouse is probably useful in answering some of those questions.
In reality, notation is in the eye of the beholder. Some people like brackets and braces to split up the flow, where as some prefer whitespace as delimiters. There are papers out there on this (which I can't find right now).
Notation is for the most part boring. The way you write function literals has no effect on the semantics of the language.
The prototype inheritance is also boring, the small step semantics being two inference rules[1].
JSON-style literals are what. A way of writing a POD. Who cares. It is boring.
Asynchronous execution is also boring. It was novel in the 1960s, it is not novel now.
[1] - http://www.doc.ic.ac.uk/research/technicalreports/2008/DTR08...