I am fairly new to R, but the more use it, the more I see how powerful it really is over SAS or SPSS. Just one of the major benefits, as I see them, is the ability to get and analyze data from the web. I imagine this is possible (and maybe even straightforward), but I am looking to parse JSON data that is publicly available on the web. I am not a programmer by any stretch, so any help and instruction you can provide will be greatly appreciated. Even if you point me to a basic working example, I probably can work through it.
Answer
RJSONIO from Omegahat is another package which provides facilities for reading and writing data in JSON format.
rjson does not use S4/S3 methods and so is not readily extensible, but still useful. Unfortunately, it does not used vectorized operations and so is too slow for non-trivial data. Similarly, for reading JSON data into R, it is somewhat slow and so does not scale to large data, should this be an issue.
Update (new Package 2013-12-03):
jsonlite: This package is a fork of the RJSONIO package. It builds on the parser from RJSONIO but implements a different mapping between R objects and JSON strings. The C code in this package is mostly from the RJSONIO Package, the R code has been rewritten from scratch. In addition to drop-in replacements for fromJSON and toJSON, the package has functions to serialize objects. Furthermore, the package contains a lot of unit tests to make sure that all edge cases are encoded and decoded consistently for use with dynamic data in systems and applications.