"Renaissance" is probably the invention of the editor at the English version of al-Ahram, who put a flashier word in the headline.
Morsi could bring about a revival. Let us remember that Muslim Brotherhood was radicalized because it was driven underground; now that they get to actually govern the country they might suddenly grow up. Whether they do, is to be seen.
Not going to happen for several reasons.
1) The MB has spun off dozens of radical terrorist splinter groups over an extended period of time, but this has not in any way increased the MB’s moderation. It continues to spin off such groups.
2) The MB’s reach is multi-national, so while Egypt is its largest branch, it cannot unilaterally change the policies and ambitions of MB as a whole.
3) The MB is under severe pressure from the far more radical Salafist movement, that will not tolerate variance from traditionally ineffective Islamist methods.
4) Egypt is a basket case of a country, with some terrible and unique problems, like 10% of the country being infected with hepatitis. (With the current breakdown of their medical system, this and other diseases are likely spreading at an even higher rate.)
This is not something that politics can readily fix. Nor is Egypt’s huge debt and needing to import most of its food.
The bottom line is that Egypt’s 80 million people are heading for a disaster, far beyond the ability of the MB to fix. Something has to give, and soon.