One problem with 'pixel-fitting' is that certain letterforms will appear sharper or crisper than others. For example, in the article the PLUS (from Hulu Plus),

One problem with 'pixel-fitting' is that certain letterforms will appear sharper or crisper than others. For example, in the article the PLUS (from Hulu Plus), the PLU are sharper than the S because more of their outer surfaces conform to square pixels, while the S has continuous curves that have to alias all the way around. So you end up with some characters looking overly crisp while the S looks soft. I prefer to not draw attention to specific characters and have consistent aliasing across all the characters of a logotype. Photoshop has several font rendering modes that let designers choose how aliasing is rendered (Strong, Crisp, etc) to achieve a desirable result, depending on the typeface and font size chosen.