The patch release date is on the page from which you downloaded them. For example:

ESX-1541239 Patch | 03/29/07 | Critical Patch

Patch Number 1541239 is a critical patch released on 3/29/2007. I usually grab all the patches I need from the particular release date, then apply them in numerical order. But I don't think the numerical order matters as long as you have the chronological order correct.

I think VMware is really getting lambasted over several issues dealing with patches. There seems to be no rhyme or reason to the patch number, we have no advanced knowledge of upcoming releases, and applying the patches to numerous hosts is somewhat cumbersome.

I wouldn't be surprised if they don't make patch management a very high priority.