Yes, there are at least 3 different strains available - PV, PJ and PA. Unless I'm going after a very mild blue, the PV is my first choice for most blues. PJ has a slower growth rate, a weaker color, and is a milder flavor. PV is more proteolytic and therefor produces a creamier cheese. Suppliers don't always carry all of these strains or they may not make them all available to hobbyists.
PV: Very fast growth rate; strong blue flavor; bluish-green color. Very creamy consistency, e.g. Edelpilz, Roquefort and strong Gorgonzola type.
PJ: Fast growth rate; typical blue flavor; middle-green color. Can be mixed with PV, no unbound moisture, long shelf life, e.g. Edelpilz or Roquefort.
PA: Very fast growth rate; mild blue flavor; dark-green color. Mild cheese, can be mixed with PV, long shelf life, e.g. danish blue and double-mould-type cheese.