LOL. Not grumpy. But I do need a holiday. =-)
I realise the shots aren't meant to be artistic, but either that lens is soft (unlikely) or the guy taking the pics wasn't terribly careful about the focus. I've only looked at a couple in detail (limited bandwidth here at work) but the one with the leaves seems out of focus, and the one with the woman looking to the left of the camera isn't very sharp. (And as an aside, even if he wasn't trying to be artistic, just a little nod towards pleasing composition would be nice… it is a photography site after all.)
I've just been across to the dpreview forums (Sigma) and it seems that most people there are in agreement. A number of DP1 users are unimpressed by the samples.
Anyway, time will tell.
Will try to make my next post especially cheery. =-)
Cheers, A