fwiw, Lego Pirates will be on indefinite hiatus from mid 2010 onwards:
http://brickset.com/news/article/?ID=372You could always pull up a couple of comparisons where Lego follows PM's lead (eg, in construction):
PM 3262 Electric Crane (2003)
LEGO Tower Crane
http://brickset.com/detail/?Set=7905-1 (2006)
PM 3263 Cement Truck (2003)
LEGO Cement Tuck
http://brickset.com/detail/?Set=7990-1 (2007)
-however, there was a simplified on released in 1985
http://brickset.com/detail/?Set=6682-1You can go to brickset's database and look up sets/themes, and when they were released by year (wished there was a similar site setup for PM items!), or what sets in each theme were release for any particular year. I've just picked 2 that so happen to show PM's earlier introduction.
My interest in Lego has been mainly the Technic and Creator/City range, which is a little hard at times for a direct comparison with PM, theme-wise - for the boys we've given in a little and let them pursue the Star Wars range (not just a licensed product, THE licensed toy product! ack! what am I thinking!
) - so with somewhat a foot in each boat, I can't help but notice that it is a little more than mere coincidence - I'll put it this way: there are quite a couple of times when our 9 year old would say something like "cool, Lego's finally got this (which PM has a similar product).
my 2 cents ...