This issue is still unresolved and after quite a bit of Internet research it seems that there are quite a few people with this issue. I can't believe that more people aren't on here complaining about it!?
I did however, manage to find a workaround which was mentioned in a couple of places on the net; once you've started Ubuntu, log off and on again, then VMWare Tools starts automatically.
I also found this which shows some merit, however there is already a vmware-user.desktop file in the specified location; it is a shortcut to a file elsewhere.
https://bbs.archlinux.org/viewtopic.php?pid=1081629#p1081629
I tried adding another file with the specified contents but it didn't help unfortunately (in fact it broke the log out/in workaround!). Maybe someone with a little more *nix experience might have a bit more luck with this?
Edit: Hmm... after re-running 'sudo vmware-config-tools.pl' and answering 'yes' to the 'Would you like to enable VMware automatic kernel modules?' option, installing some Ubuntu updates, adding the above 'fix', rebooting and then removing it again, my VM now starts VMWare tools automatically on boot!? I've re-created this on another, identical VM, but I'm still unsure which actions re-produce the fix.
My suspicion is that it's the vmware-config-tools.pl (possibly with the 'enable VMware automatic kernel modules' option enabled) that did it. I'm pretty sure that the updates were run during the reboot after I made the config change, so it's hard to confirm whether this made any difference. However, during the re-creation on my 2nd VM, the updates by themselves made no difference; so either it's a combination of both or the updates aren't involved.
If anyone can confirm this I would be greatful!
