LJ has three killer aps:

1. Icons. Okay, I’ll admit I’m not an icon user. I have four icons on LJ, and I only use one at a time. I basically don’t care much about icons. But, people on LJ are crazy about them. Pay lots of cash for extra ones, etc. While icons make LJ quite a bit of cash, they also are not free because they supposedly impose a lot of strain on the server. WordPress does allow you to have an avatar, but only one, while LJ allows free users six, and paid users many more.

2. The Friends list. Okay, the friends list is basically a feed aggregator, but with authorization permissions. In other words, you can access controlled material. There are many feed aggegator programs, but there are no feed aggegator websites that allow you to do auth permissions. (In other words, web-based third party).

3. Friends-lock. In other words, authorized viewing. WordPress has this in plug-in form, but you need to have it on your own server. On the wordpress.com service, you can allow your blog to be seen only by 35 people for free (in other words, have 35 authorized viewers), or you can password protect individual posts. So wordpress.com is even less social-networking oriented than LJ.

Also, these are not specific to LJ, but are advantages it has over wordpress.com

4. Threaded comments. WordPress doesn’t seem to have this feature, which makes it harder to have discussions.

5. Price. WordPress’s features seem to be more expensive than LJ’s, and do not come bundled.