One of the reasons I wrote the book was to kind of lower the barrier of entry for writing or enhancing a JavaCC grammar. Right now the documentation for JavaCC is not bad if you can pull it all together, but that's just the thing - it's scattered all over the internet. The documentation on the JavaCC site itself is good but it's really heavy - it throws you right in at the deep end of the pool. Hopefully "Generating Parsers With JavaCC" can make this excellent tool more accessible.
There are a slew of JavaCC grammars all over the place - grammars for Cobol, C, BeanShell, Oberon, XQuery, VHDL, ASN1, PHP, VB, Java, EcmaScript, and even LOLCODE. JavaCC continues to move forward; it generates parsers with Java 1.5 features, the users' list has some savvy folks on there to answer questions, and we've been discussing various improvements on the dev list. I see good times ahead for JavaCC, and hopefully the book can contribute to that success a bit. Go JavaCC!