Aside from the cheer, good eats and great music, holiday parties are also an excellent forum for conversation. As part of a great Toastmasters club here in New York City, I look forward to these discussions because my fellow members are diverse, intelligent and thoughtful. This year, spontaneously, one such conversation focused on the change in how people viewed themselves in the context of their work.
My grandfather was a loyal, decades-deep veteran of a well-known insurance company up to the day he retired. He still speaks fondly of his time there. While the ambition to "get ahead" has not changed over the years, how professionals conducted themselves in that process has definitely changed since my grandfather was a "company man". In his day, I'm fairly certain that personal brands were not discussed as anything more than theory; now they are considered by many to be vital to professional success.
There is a lot of solid thinking that goes into this concept (not to mention, actual results). However, your content is an extension of your brand, not the brand itself. Does that mean that it doesn't have to be consistent? Of course it does. Does that mean that it shouldn't reinforce your brand's values? I think it would be silly if it didn't.
Content and content creation are in service of an identity. For example, when you're on stage, it's not enough to simply read the words on the page, you have to make the audience believe that you believe what you're saying. How you achieve this is going to be unique to you, but it starts with genuine belief.
Serving an identity requires you to interpret your content correctly. For example, Pharrell Williams has made music with dozens of big names over the course of his career, and while some sounds and techniques are in common, the songs he produces for Jay-Z sound very different than the work he does for his own band, N.E.R.D. This helps build his identity: someone that can fit many styles, rather than settling for impresario status over just one genre while sacrificing musical range.
You are an individual. You have an identity, and you have something to say. Let the brand be consistent, but for the good of the brand, let your identity be dynamic. Your content will thank you.