I read livejournal so rarely now and often just skip over whole chunks of text. Most of the people I deleted were people that I don't read anymore. No matter how witty or interesting you are (and there are several whom I deleted who truly are intelligent, witty and funny), I'm spending less time at the computer and I don't want it to feel like a chore.
These deletions may match up to a couple people who have deleted me. It's not vindictiveness. It mostly comes down to reading habits and a sense of feeling exposed by allowing my friends-only posts to be read by people with whom I don't keep up myself.
I thought about deleting a few more, but the social backlash is undesirable. Instead I will continue to use the filters that I have erected. I often just read a single person's journal a night rather than using the livejournal friends page feed. It feels too pressing and overwhelming to read them all.