Thanks everyone for the feedback - it's interesting to hear the different approaches.
I'm finding that DevLog + Twitter is keeping me busy enough and I think I'll have to duplicate some content. I'm holding off from creating an IndieDB entry for my new game until I'm a bit further down the track.
A DevLog and Twitter account is great but have you considered using a Facebook fan page? It's a great tool in the marketing arsenal that rounds out some of the drawbacks of a social media platform like Twitter. Also, do you have plans to convert followers and readers into a mailing list?
As for how to curate content for all of it. There are a couple schools of thought. One is unique content depending on the marketing medium (facebook is a different type of content then twitter which is different then tumblr or a forum so on and so forth. You get the idea). The one that I find is more realistic for indies that dont have a community manager is to re-purpose the same content over as many platforms as possible. This will definitely give you the largest reach with the shortest amount of effort. Keep in mind that you may have some followers that are really engaged in twitter and some that are huge into indieDB if you create equal content for the different platforms (even though it may be the same content) you are allowing your fans to consume your content where they want to and where they feel comfortable to engage in a conversation.
By re-purpose, do you mean copy/paste the content? I would argue that this tactic can be a double edged sword if you're on more than a couple social media sites. While it can save time to recycle the same post you put on your DevLog across all your marketing platforms, it can de-incentivise those who may follow you over more than one platform. After all, why should one follow your fan page and have your posts take up their newsfeed space when they can see the same exact same post from Twitter?
If you're still strapped for time and find it easier to use that strategy, by all means use it if it keeps you posting out there. I would just recommend modifying it a bit so you don't copy/paste the same content across all platforms at the same time. Take a few extra minutes to reword the content for each place you post and put a little time between them where you can. A pita made a great suggestion with using
HootSuite to help manage what you share, I've been using it for social campaigns for a variety of jobs and projects.
Post Planner is also a great alternative.