As you can see, a lot of links are coming from Google, so looks people are searching for stuff, and finding the blog appear on the search results, and find their way here.
For example, if you search for "oracle business intelligence", while the first couple of results are from Oracle.com, the third hit is from the BI Blog.
Also, Mark Rittman's blog is a popular blog that people come from.
At the risk of extrapolating the last 100 hits to be representative, it seems that more and more hits to the blog are coming from searches. Though I can't figure out just how someone searching for "dog food bar graphs" landed on this blog! Search and you find that this post is the culprit, and that too it is the second search result!
The home page of the blog is very popular, and now the last post too...