When National Australia Bank wants to break up with you a "Dear John" letter is not quite enough. To really get the point across it needs to go on a media buying spree - taking full page ads in national broadsheets, airtime on radio, outdoor billboards, mobile billboards, street graffiti, helicopter banners, building banners, create a website and hire street teams to help stage experiential break-up events and hand out "break up" mementos like music CDs.It also likes to make a series of viral videos taunting its jilted lovers, in this case Westpac, CBA and ANZ, and then it gets its staff, friends and family to tweet about the sad end of the affair. Should someone get an apprehended violence order?The 48-hour multi-platform marketing stunt, anchored around Valentine's Day, certainly sparked up the social media and old media channels, but the question of whether it will actually win over customers will be played out over the coming months. One thing is clear: breaking up with the big four banking cartel is an exhausting and expensive business. Will this be worth the eventual cost of acquisition per customer? The 'break-up' campaign was devised by Clemenger BBDO Melbourne, with media planning and buying from Zenith Optimedia, and public relations duties being performed by Bang PR. It was an epic feat of co-ordination and execution, and, in terms of delivering a piece of truly integrated multi-format marketing, it is something the Australian banking and marketing sector has not seen before, certainly not on this scale.The project was also not planned lightly. NAB has been beefing up its in-house digital and social media teams, hiring steadily since mid last year and innovating on the mobile application front. In late August, it overhauled its nab.com.au site, in addition to the official NAB profiles on Twitter, Facebook and YouTube. Official NAB accounts, serviced by a dedicated social media team, have been also been created on Twitter (@NAB) and YouTube (youtube.com.au/nab).All hands were certainly on deck for this project the tweets alone would suggest. But no matter how grand the marketing gesture was, the campaign's premise is not a disposable proposition. The NAB has now clearly re-defined itself as a rogue player that will lower fees, pay for the privilege of switching mortgage customers over and continue to keep the other three on their toes.In banking that's a hard promise to sustain for long. The NAB has been working on the shifting customers perception for over 18 months, implementing a series of competitive measures, such as abolishing monthly account fees, boasting the lowest standard variable mortgage rate, offering a $1000 buffer for all overdrawn fees, to help businesses, and, most recently, offering to pay the $700 mortgage early exit fee charged by CBA and Westpac for customers switching their mortgage to NAB. It is unfortunate that the bank's digital overhaul was marred by its massive technology fail in late November, which took the bank nine weeks to sort out. NAB was universally panned for lack of communication on the reasons