I like it for the most part. It's bold and bright. However, I would reduce the contrast of the background to make it more one colour perhaps with subtle clouds, right now the contrast between the blue and white clouds is too distracting from the content. Apart from that the green colours are very appropriate. What draws your attention first is the top post title which is good, but the sidebar containing categories etc is a little busy and confusing. Also I would consider increasing the text size of your categories text.
Hope this helps
