[arun_sriniv]

We're in the process of adding more detailed vignettes illustrating more clearly the philosophy behind data.table's `i, j, by`. Should make things lot easier for beginners - https://github.com/Rdatatable/data.table/issues/944

data.table is not just fast, but is also more memory efficient - we want to highlight in the vignettes as well.

And timings are quite relevant even on 10 million rows: https://gist.github.com/arunsrinivasan/db6e1ce05227f120a2c9

For much larger data, check the project page: https://github.com/Rdatatable/data.table/wiki/Benchmarks-%3A...