I use a plugin to post to twitter every time I post a blog post. I also have Facebook pull in my new posts and notes. This works reasonably well and I get some traffic from them.
You can also use twitter tools to post your tweets on your blog after a certain threshold. I don’t use that because I want to keep things separate. I’d rather have a block that shows my latest tweets somewhere.
There are so many ways you can cross post from your blog to twitter to Facebook and LinkedIn. For me personally this is too much cross posting of not too related content. Let me explain.
On twitter I have mostly techies, locals, bloggers and new age marketers. On Facebook I have friends and family who for the most part are not techies at all. On LinkedIn I have co-workers and professionals.
So for me at least these networks mean different things. I saw a tweet yesterday on LinkedIn it was a personal quote about love. Also when you see auto posted blog posts with tweets and link bits it seems less personal and mechanical. You know the blogger hasn’t taken the time to write something.
I prefer to post separately to each network depending on what I have to say. This is except for getting link backs for my blog posts which I mentioned first.
I’m sure there are people with a consistent profiles across networks that pull this off well, but I’ve yet to see one.
My 2 cents is keep things simple and think of the audience for your post before you setup automatic cross site posting.