Write your own blog. I know it's an unnatural experience for those of us who would rather have our heads down coding, but it's worth it for several reasons:
1. You blog should speak with your own voice. Nobody can replicate your passion for what you're doing.
2. Nothing will help you refine your message more than trying (and initially failing) to communicate it.
3. Like it or not, your startup's success probably depends more on your ability to communicate than on your ability to code (you can already code, or you wouldn't be here). Doesn't mean you have to be awesome at it, but you do have to be good enough to get people to listen to what you're trying to say.
4. When, after lots of practice you do get good at it you'll actually start to enjoy sharing your thoughts with the world.
I don't necessarily think that you need to write the blog posts, but I don't think that they should be outsourced to someone that is not familiar with the inner workings of what your company does. The person writing the post needs to be passionate about what they are writing about and needs to be on the pulse of what is happening with your company and the industry. Yes, you could do it. But the truth is that doing a blog and managing your overall communications is a lot of work in and of itself, and could eat up a lot of your day. This could be fine if you have the time to devote to it. But don't be half hearted about it.
I see a lot of startups put all of their early funding into dev resources, thinking that they can just pick up the slack on the marketing side. The truth is that marketing/communications is a make or break issue for your startup. You could have an awesome product but if you don't get the word out and build/manage a community around your work, you aren't going anywhere fast. So, my advice? If you don't think you will have the time to be truly committed to doing it right, hire someone that has a background in communications to join your team. Don't treat your marketing strategy like a second class citizen.
If you're blogging for traffic/links ala Mint.com, you can outsource it. Mint outsourced their early blogging to a finance blogger they found.
If you're blogging for B2B customers, or to become a thought leader, outsourcing can be tougher. It still can be done, but it's tough. Many ecommerce/web marketing companies with successful blogs have outsourced most of the content creation, or use multi-author blogs.
1. You blog should speak with your own voice. Nobody can replicate your passion for what you're doing.
2. Nothing will help you refine your message more than trying (and initially failing) to communicate it.
3. Like it or not, your startup's success probably depends more on your ability to communicate than on your ability to code (you can already code, or you wouldn't be here). Doesn't mean you have to be awesome at it, but you do have to be good enough to get people to listen to what you're trying to say.
4. When, after lots of practice you do get good at it you'll actually start to enjoy sharing your thoughts with the world.
Good Luck-
- Ben