- You have only limited space to tell the reader everything you want to tell. For example if you put labels and archive you don't have very much more prime real estate on top of the screen to put anything else.
- You have limited space to put ads on your blog. You have to either put it in your post or you need your ad to occupy the prime real estate on top of the screen making it look like all you are interested in is advertising.
I am not sure why blogger has only 2 column layouts as default layouts. They are not really providing variety to the blogger out there other than in colors and styles. If you look at all the bloggers who are serious bloggers like Amit, Darren and Abhinav all have 3 column or more layouts.
What I have realised is that readers basically read a blog in a top down fashion. They first go top down on the main post column and then they move to the other columns looking for more to engage themselves. So you need to have good stuff on the tops of your columns to keep them engaged. If you have only 2 columns then you are limiting yourself in keeping your readers engaged.
As I am moving from a 2 column layout to a 3 column layout you may realise some broken or ugly looking sections so please bear with me. I would like suggestions and criticism as i move from my older layout to the newer one. So feel free to leave your feedback.