Let me begin by saying I love comments on this blog. Let me re-phrase. I love relevant comments from interested (and interesting) parties. With that in mind, I'd like to outline some points that may make clear to some readers why their comments are or aren't approved and published.
1. Share an opinion. Tell me what you think of a post and/or recipe, even if it's not a positive response, but please be constructive in your criticism. I am more likely to approve a comment which says “I'm not sure about this because I hate x ingredient and I don't think that's an appropriate cooking method” over “this is stupid and you're a poopyface.” Yes, I have actually received comments of this nature.
2. Share relevant links. Do you have an alternative recipe or a suggestion for something else? By all means, share a link to your (or someone else's) site, a photo, or whatever you think is relevant. Chances are that sort of comment will be approved because it has meaning and adds value to the post. Comments which exist purely as a means to promote yourself with little regard to the original content, however relevant the link, will be edited or not approved.
3. Don't share irrelevant links and/or information. Don't come in and make a half-arsed comment about liking a recipe and then saying “by the way, have you heard of this website? You can buy pots and pans for cheap.” Translation: do not try SEO tricks by spamming my comments with links to your new site. I will not approve any such comments because they simply aren't relevant and will automatically be marked as spam.
Try to think of blog comments as if you're having a face to face conversation. If I tell you I've written a new recipe and your response is “please look at my new dating site,” I'm going to give you a funny look and walk away.
4. Do your research first. A quick glance at the about page would tell you I live in the UK and I'm vegan. Do not contact me about American products or with news of a brand new dairy company.