Probably your site is going crazy, it’s wrongly displaying multi-line text fields and you’re asking yourself, who stole my new lines? Well this issue could be related to Sitecore upgrades.
Recently, I read a post regarding a small, but important, change at FieldRenderer that might impact page’s presentation when Sitecore is upgraded from 6.2 to 6.3...
Sitecore 6.3 removed the new-line character from Multi-Line text fields. This change might impact your page if you’re using the ‘\n’ char replacing it by ‘<br />’ tags or using it to split the text in an array of lines.
If you need to work with the new line char, you can get it using raw value of the field’s Value, which is still containing the ‘\n’ char. Remember the char is removed by FieldRenderer.
More details at the original post.