i just picked up the 70-200 f/2.8 because the price was hard to argue with. Testing it out vs. the f/4 IS. I actually did some test on a tripod, and turns out, it wasn't the lens, it was me (or the tamron 1.4 TC) that was softening up the image.. 
now i have to decide which 70-200 i want to keep.
and yeah, it was Balsa Chica. 200+1.4TC was *almost* enough, but something longer would have given me a lot more latitude in terms of how i want to frame it.
There was a blue heron there too, but it looked almost injured. slow moving, and the feathers were very ruffled.
This was actually the first time i've been to the spot, even though i lived in HB for 4 years.. just re-picked up photography for a hobby not too long ago.. 