nError => onError ;-)

You could differentiate here: instead of startWith(T), use +:, and instead of startWith(more than one T), use Observable.items(...) ++ o

Thanks. Already updated it.

The idea of this table is to have one row for each item, so you should split this into two. Also, when editing this code, from time to time you should run printMarkdownCorrespondenceTable, and convert the markdown to html and check if the generated html looks nice.
And you're also welcome to make PRs against https://github.com/RxScala/RxScala.github.io so that your updates are actually read by visitors of the http://rxscala.github.io/comparison.html page ;-)

Updated it. I'll send a PR to RxScala.github.io once this one is merged.