From my understanding, a high bounce rate for a blog isn't necessarily a red flag.
Let's say someone from Google landed on one of your posts/articles. They read it then leave. They may have found exactly what they were looking for and just not navigated any where else on your site. How long are people on your site? If you have a high bounce rate and a very low page visit time average then I'd worry more. How fast do they "bounce"?
I'm curious if your sharaholic widget at the end of the post interferes at all. Technically they're leaving your site since it's being redirected through the shareaholic links. They come back but it's all in the same window so could count as an exit. I'm not sure if return visitors are excluded from bounce rates.
My goal would be, "how can I increase a visitors click through rate?" A call to action button at the end of the post? Something to funnel those readers that want to be there to continue to another page instead of closing the window. If you liked that... check this out....
I didn't encounter any pop-ups and page loading time was great. For me, there wasn't anything that scared me away (quickly) if I had found what I was looking for.
I have 2 little suggestion: looking at your Popular, Recent & Comments module/widget on the right sidebar, that would be a good one to tinker w/and highlight more. If the thumbnails were larger, it would draw your eye more. Maybe 100 or 125 px width images instead of 60 px. Plus maybe adding a tag cloud. Those are so quick and easy to use for visitors.