On NETTUTS.com there's a new tutorial talking about the problem with PHP's prepared statements, mainly due to their flexibility.

There are a couple issues that appear to make these methods less flexible than we’d hope. For one, we must utilize the bind_result method, and pass in a specific number of variables. However, what happens when this code is within a class, and we won’t immediately know how many variables to pass? Luckily, there’s a solution! I’ll show you what it is in today’s video tutorial.

The tutorial is screencast but they've also included the full code ready for cut and pasting into your favorite editor of choice.