Great thread!
I have been blogging for two years in April and have steadily increased my following and comments. I still have a long way to go but my blog and the following it has makes me happy.
I recently went on a trip with Not Quite Nigella (Lorraine) www.notquitenigella.com.au and she taught me so much about the business of blogs. I realised at that point that I was not as dedicated as she was and I was happy to grow slowly.
Some of the pointers I gleaned: If someone does comment on your site you should always go to theirs, read their work and comment too. Ie: I should now go to each persons website that commented on this thread and build and interaction.
Ask a specific question at the end of your story to encourage comments.
Chose your stories carefully, know your audience and your style and don't alter it too much. Keep your stories on the shorter side (I am not good at this and NQN commented that neither is she.) Always be honest on your site and gracious. Help others coming into blogging, it really isn't a competition, plus the ones you help will talk about you and your site and may ended up inviting you places in the future.
Blog regularly, it doesn't matter if it is daily, twice weekly or weekly but you need to commit to a regular pattern so that your follows know when to look for a story from you.
Don't just post a story and hope people find it. Announce it on your facebook page and tweet about it. You are your own publicist! Find any social media outlet you can to announce your story to.
I have a PR company who found me, they provide samples, giveaways and the odd trip so I want suppliers to get their monies worth from my site. That means I need to talk about my website to as many new people as I can so that readers will also see any adds or product endorsements I am running.
I hope some of my ramblings are useful.