Over the years I have had some great conversions (normally heated) and challenges related to the use of Keywords Vs Branding, this excellent thread poses some options for title tags on your website.
When looking at it purely from a search engine perspective though I would argue that Keywords should always win first. When arguing this point with a a “Marketing Guru” I tend to get them to understand that search engines are the method of getting your customers to your marketing message, which in this case is the website. This is no different from using postal services to deliver personalized mail to your database. The personalized mail is the marketing message, the postal service just puts your message under the noses of your customers.
Your branding will always be better reflected on your website anyway, and as such, you have control over images, design and words/phrases which reflect your brands message. So you should focus on improving the sites ability to be ranked well in search engines, as this will supply a nice amount of traffic/qualified leads to your site, who can then interact with your brand.
Most brands, if unique will naturally rank well on their own, without the need to worry about ramming the brand message home in every conceivable way. If you have a real unique catchphrase, that potential customers are going to search for, then be all means ensure those keyword phrases are included. But rather than thinking about search engine optimisation (Optimization, SEO), as a marketing tool, consider it the process of delivering qualified leads to your website, the point upon which the brand awareness should really begin.
Your website will always have brand dominance, as you control the real estate. So don’t try to battle for brand positioning on search engine results, your message will always have to compete and most often will be diluted.