I can see why they're doing it and in some ways it's a good plan to free up space etc, but I just hope they do it really, really carefully.
In case people were wondering, LJ have updated their wording on what is an inactive journal because of feedback and it is now this:
"A journal is defined as inactive if it has not been logged into for 24 consecutive months and has only one post (i.e., the welcome post). A community is defined as inactive if has not been updated for 24 consecutive months and has only one entry and no comments."
I hesitate to say it, but it looks kind of sensible.
What might be a really good idea, however, is for LJ to publish a list of all the accounts they intend to purge in the two week period when they send out emails so that people can check. Belt and braces never hurt in a case like this.