Even before the closing ceremony had finished, there had been much talk of what shape or form the Olympic legacy may take. There is, without question, a renewed sense of national self-confidence and a groundswell of united pride, the like of which hasn't been seen since the Thatcher government successfully liberated the Falkland Islands in 1982. The general election of 1983 returned the Conservatives to power so ardently that a shakey Mrs Thatcher became the Iron Lady and received a mandate for change which eventually led to the socio-economic reforms which inexorably altered the nature of the UK's economy for good. Together with Charles and Diana's Royal wedding of the previous year, Thatcher's government presided over a period of renewed national fervor and converted this into stunning electoral gains.
It is difficult to see what could possibly propel Cameron to such heights in the electorate's regard. As discord over the EU, the financial crisis, swinging cuts and Cameron's inability to understand that liberals will never vote for him (and Conservatives might stop doing so) continues to grow then the party may well look for new leadership. Johnson's unashamed Etonianism will appeal to the small 'c' conservative core of the Party in addition to the rest of the country's new found love of the man. In answer to the articles chief question, it may just be that whether Mr Johnson wants it or not, his inexorable rise might take him to the very top and inherit the Conservative Party leadership. He has become Cameron's Hesseltine, the de-facto stalking horse for any leadership contest of the future. That said, he would first need to be an MP or a member of the 'other place' in order to become PM and for that, he would need a constituency that would vote for him as well as a sitting MP prepared to stand aside and force a bi-election.
Thus, Boris for PM? Maybe, one day, but not yet. First, Cameron would need to be pushed out and a constituency seat must become available.