Soft crust, tangy sourdough flavor makes this one of my favorite sourdough bread recipes.
A response to those who feel the bread is not sour enough. The taste of the bread relies heavily on the 'sourness' of the starter, which varies from area to area. Here is a suggestion from King Arthur Flour on making bread 'more sour', hope it helps:
In general, you can achieve a more sour taste by allowing the dough to ferment for a longer time at a lower temperature. However, the climate you live in and the strains of wild yeast naturally present in the air around you also influence how sour your bread turns out. Some bakers add some extra zing by adding "sour salt" -- not actually a salt at all, but pure citric acid. (This is available through mail order from The King Arthur Baker's Catalogue(R) at 1-800/827-6836)