Write something useful for yours reader. Share a relevant piece of information, an event update or a hack that makes a task simpler.
Avoid using SMS abbreviations in blog post and at least run the post through a spell-check in MS-Word before publishing. If the bloggers cannot take the time out to write proper English, why would the readers bother reading through that cryptic puzzle?
Interact with your readers! Reply to their comments, emails and queries. Acknowledging your reader will make them come back to your blog again and again.