My blog is at bjornlee.com and I noticed my sidebar completely disappeared one day upon loading, only to find it slipping towards the bottom of the page. My cntent posts are also "overflowing" outside the normal confines from the 3rd post onwards. You can see this all on my site. I was using the Freshy Theme. Changing themes did not help.
I was using Version 2.1.1 and tried upgrading to Version 2.1.2 last night but the problem persisted. Prior to noticing this problem, I never made any changes to the CSS layout themes. I tried searching the support forums here for "site layout screwed" where the problem was linked to oversized pictures or posts. I tried deleting these pictures and posts but it did not work out too.