It's not a minor thing. It's bad design. The primary content of a page should always be at or near the center of the user's view. Currently, on my laptop or television, the stream is all the way to the left of the screen minus about 100px, meaning I have to actually turn my head to see what is supposed to be the most important content.
Making the text of comments gray is also a problem. Again, this is primary content. Reducing contrast not only makes content harder to read, it's an indication that the content is disabled or unimportant. All content text, including comments, should be standard black-on-white. To distinguish names, which are currently black, from the content, they should be made either bold or blue (as they are when you move the cursor over the comment).
These are very basic and common-sense design considerations. The rest of the new layout is fine. But these two things need to be addressed.