Corporate earnings have surged and stocks have soared, but the housing market is still weak. Interest rates re...main low, but are rising. Many countries' economies are perking up, but a jump in commodities prices is producing inflation. Governments in the United States and Europe are wrestling with huge budget deficits and debt problems. For insight, Knowledge@Wharton talks to Wharton professors Jeremy Siegel, Franklin Allen and Susan Wachter.