Just an idea I had today for improving the site and identifying answers to your question that are more likely to be valid. The idea is that if the answering user has a badge for any of the tags that are present on the question, indicate it somehow on the answer.
This sounds similar to the idea of following certain users, endorsing certain users, or marking certain users as trusted users. The problem that I see with such features is it creates a bit of an exponential effect on one's reputation score and can actually artificially inflate a post to make it seem more useful than it really is simply by association with a specific individual.
Since the content is the most important creation of Stack Exchange, it's critical that the content continue to stand on its own merits. Branding an answer based on a user being active in that tag may detract from that content.
In short, just because you've answered more Java questions than me doesn't mean that I can't contribute a valuable solution that is also the best solution.