I seriously find it difficult to believe that this is still a debate on YC. Once you attempt to build a site of a reasonably level of complexity and/or learn how to build a site using clean, valid, semantic markup, you'll never go back - unless horribly messy code and hack piled upon hack are your thing.

This isn't about being a web standards zealot. It's about learning to do your job. Look to any of the industry leaders in frontend development - it is simply no longer an issue. Table-based implementations of layouts (and all non-tabular data) are the GOTOs of modern markup.