Bernanke is well respected by economists.  Paul Krugman, for instance, has indicated that he would be comfortable with a Bernanke fed chairmanship (on the condition that Bernanke not do idiotic things like endorsing irresponsible tax cuts ala Greenspan).

It is very important to note that fed picks are something presidents absolutely cannot screw up.  If Bush picks someone that market views as unqualified, markets will crash and the US will lose foreign investment.  Basically, there are big economic implications to the fed pick.  If you think the revolt over Miers is big, it would be nothing compared to the chaos of him appointing a Miers-like fed chair.

 Instead, Bush made the best choice he could by picking a person almost universally viewed as high qualified, and someone who is relatively close to him.  Note there are people who are cozier with Bush, such as Hubbard, that the market wouldn't have supported.  So i suppose he deserves credit, but its hard to give much credit for making an obvious, and rational choice (something we should be able to expect, but unfortunately aren't able to with this president).