Mark, I use posterous for quick posts. Try it and within minutes you'll have an account, your first post will be up, and (if you hook it up to twitter) you'll start getting both traffic and comments quickly.
I love Tumblr, but for quick posts, posterous is dead simple and very fast.
I really like the interface of Tumblr. I do resize uploaded photos myself before I post them there, though, I like a consistent image size.
I set up a Posterous blog for a committee I'm working on. It was easy to set up and password protect, and I can attach .pdfs to an email and send it in to be posted within a scribd viewer.
If I was just going to be writing and linking and such, I'd go with Tumblr.
I use Posterous because I like the auto-post feature. Tumblr has more features and is more "pretty" but I think Posterous is easier and simpler.
It's not exactly a blog but I think friendfeed would be much better. Plus It has got a great social aspect and supports other micro blogging and normal blogging tools, websites.
Why have 2 blogs? It is confusing for your followers.