I'm equally proficient at front-end and back-end, but the last time I did a whole bunch of interviews, I advertised myself as a front-end programmer (since there aren't too many full-stack positions around).
Why? As a back-end developer, you're limited to picking companies that match a single one of the three broad back-end categories -- generally Java, Microsoft, or "open-source" (PHP/Ruby/Node/etc.) -- since any programmer is usually only going to be really proficient in just one of those. If we assume companies are split 3-way, you're instantly limiting yourself to 1/3 of possible companies.
But on the front-end, there's no balkanization. It's just JavaScript, JavaScript, JavaScript. It's not too hard to learn JavaScript and jQuery inside and out, and with some solid CSS experience, knowledge of good development patterns, and maybe a framework or two, you can interview practically anywhere.