I guess I'm in the minority based on the other comments here…
After spending a few hours with the documentation, I felt like I had a generally good feel for how you would interact with ES through curl, but then jumping into using the Ruby library there seemed to be a big leap and I felt like I needed to have a much more intimate knowledge of how ES worked to "get" it. A lot of guess and check before I figured out how to query properly. I've also been unsuccessful in figuring out how to implement accent folding. At this point I assume that this has something to do with "mapping", but I couldn't figure out where that was supposed to be set up (again, through the Ruby lib, but I was also unsure where to start to just accomplish that via curl…).
Who knows, maybe I just need to spend more time reading the docs, and maybe the information that I need is in there somewhere, but to me it felt incomplete or disorganized. I'd love to stop using Solr for document search, but making ES do things that I know how to do in Solr ended up being too time consuming.
I ended up feeling like I probably had to go to a training session to really get it, which is a shame…
I found the elasticsearch tutorials on youtube by Clinton Gormley pretty helpful in understanding the concepts. Also came across this book (which I haven't really read so I don't know how good it is, just posting it here)
http://exploringelasticsearch.com/
I don't know OPs pain points, but mine were quite simply that the query DSL for ElasticSearch seems to be a thin wrapper over Apache Lucene. If you have experience working with Lucene, picking ElasticSearch isn't that difficult. If you've never worked with Lucene before a lot of the concepts aren't necessarily obvious, and it's incredibly easy to write queries that won't return what you expect but won't fail either. My experience trying to configure analyzers and trying to adjust search parameters involved a ton of trial and error.
