For example, DFH 60 and 90 Minute, as opposed to typing out Dogfish Head. Of course it's not much effort to type out the full name, but many existing discussions about beer on the Internet use such abbreviations. Should we refrain from abbreviating so as not to exclude beginning enthusiasts? Or should we follow suit to keep up with the culture / adapt beginning enthusiasts to modern lingo?
The standard rule of thumb is that you should never abbreviate the first usage of a term of art in a given piece of writing/post/internet discussion. After that, go nuts.
I see no reason to deviate from that standard here.
If it's the name of a brewery then it shouldn't be abbreviated, as not everybody is from your area. (I for example, have never heard of Dogfish Head).
An abbreviation like DFH is also not easily googlable.
What is "commonly known" in one part of the world may be perfeclty unknown somewhere else. The best thing to do is to avoid abbreviations and acronyms. As a second best, one could make them explicit at the first usage, as suggested in another answer here.