Look when my last post was...3rd September, a whole THIRTEEN days ago. It doesn't look great does it? It's not the worst I've ever seen, but when you commit to writing a blog you have to update it regularly. A blog is for life, not just after 'an ideas meeting where you realise you need to look personable to your customers'. Having a big gap in posts doesn't give off a good impression and makes you look distant. Imagine that the world is dying to know what's going on in your company (I mean they totally are anyway but y'know)
I'd advise that you don't give ownership to one person for the blog because then you might get the same content with the same subject expertise. Circulate it around your organisation and make it a fun thing, if you have different authors for each week then the load is more manageable and you can schedule it in.
If you're finding it tough to keep up with posts, you can always ask someone else to help out, someone like me! Get in touch.