For a counterpoint: * you can get "EBNF"-style operators using traditional LL parsers like ANTLR. * Likewise, top-down parsers can have integrated lexing also

For a counterpoint: * you can get "EBNF"-style operators using traditional LL parsers like ANTLR. * Likewise, top-down parsers can have integrated lexing also. * The downside of prioritized choice is that you don't get any insight into what inherent ambiguities your grammar has. The dangling-else ambiguity in C (for example) is a real ambiguity that you have to tell your users about. Prioritized choice hides ambiguities and gives you no hint when you develop your grammars where the ambiguities are. * PEG-based parsers are less efficient than LL parsers. LL parsers are O(n) in time and O(d) in space (where n is the length of the input and d is the depth of the nesting). To parse a PEG in O(n) time the space complexity becomes O(n) (this is a packrat parser). To parse with O(d) space, time complexity becomes O(n^d) (as with lpeg). And the constant factor for LL parsing is much lower than with packrat parsing. I think the future is LL. When the tooling gets good enough with LL, I think that the primary motivation for PEGs (that they are easy to use) will evaporate.