Upload & Sell: Off
I've seriously considered an mk1, but I honestly think that I'm stupid, and fickle enough that it would bother me.
Hear hear! When I had the 17-35L, I kept obsessing about how 16-35L II is "better" and guess what... I sold my 17-35 eventually for a 16-35. So of course I've been considering the 24L non-II, the 28/1.8 and the Sigma 24/1.8... but I'm afraid I'd fall into this mindset again if I buy one of those. Even though I need this lens pretty much for my own fun, not for commercially viable work (which I'm now doing only rarely).
Of course if Sigma releases an update to their 24/1.8 with HSM as the rumors state... I might buy that one instead, since it'd likely cost $800 rather than $2000.