Essentially, here’s the criteria I would use to judge things – if your site is made up of primarily static, HTML-based content, then you probably don’t need a VPS package. However, if you have a large amount of files stored, multiple sites, dynamic content, and the possibility of major traffic from time to time, then you might consider upgrading to a VPS. It’s a powerful package that allows you to do more than you could with a shared hosting plan, but requires less investment than a dedicated server.
The answer to this question is a definitive “maybe.” Since you’re looking at this site, you might be a Web designer who has a few sites, an online portfolio, and a couple of long-standing clients whose sites you manage. Is a VPS for you? Well, you’ve most likely outgrown a shared platform, and as a professional, it won’t do to have your site run poorly because another site that you share a server with is using more than its fair share of resources. A dedicated server could be overkill – if you don’t need all the resources on a consistent basis, you may not be able to justify the expense.