I think international remittance will definitely be one of the killer apps of Bitcoin. There was actually a good reddit post/comment about it yesterday (see http://www.reddit.com/r/Bitcoin/comments/2hsj38/holy_smokes_bitcoin_im_freaking_outand_western)

However, I don't think prime time Television Ads are necessarily good for Circle. TV Ads are generally good for 'awareness' but poor for actually getting users and conversion. There are many channels they can target, for example Search Engine Marketing, SEO, Facebook/twitter ads, all aimed at the mainstream market. But the benefit is that there is an actionable task for these channels, such as a click, which is trackable.

In a few years, when Circle has exhausted all other marketing channels, then I think TV Ads will be good to keep up the general level of awareness