What resolution? I am guessing you have three options here:
1. Reduce font size for node titles (not really viable, they need to be significantly reduced)
2. Define a height for the node box that fits
3. Move the last post bit below the node title
The problem is that the node title goes over two lines on some nodes, meaning they have a bigger height than the others, which offsets them. Probably the easiest thing to do is to just set a height on the first css rule in my code.