Maybe you could trade off based on what you have to say? Like if you have some pictures to show off, you could use Tumblr, but if you have just text, you could use LJ? And cross-post a link, if needed?

It's a fun thing to do, journaling about what you did, and it makes you feel more connected and involved -- or at least it does me. :)

The important thing is the having fun, and it sounds like you're off to a good start. Keep it up! :)