Seems to me that the poll has probably always been out of date.
Each person put in what they used at the moment they were polled - but these polls were at different times, and I'm pretty sure that the majority of us have moved around quite a lot.
I tried WDS for a while, but it was always too intrusive, so off it came.
I liked GDS for quite a long while, but it wasn't just focused on desktop search and gradually felt more intrusive, so off that came too.
I tried Copernic quite often, but its a very long time since I preferred it to anything else.
I mostly use Archivarius now if I want desktop search, but I don't do it that much any more.
I do use Everything, RecentX
I do put stuff I know I will need in Ultra Recall, Evernote
I do use Mailstore (at least when I can't find an email in gmail)
I do use J River & various specialised image databases
One of the first engines was nowadays forgotten AltaVista Discovery, but it's some eleven years ago... I was even a member of the beta testers group.
-yksyks
I really loved Alta Vista Discovery when it came out (and there's an example of a company that went badly wrong when the whole world was waiting for it), but there was less stuff to search then, even though it felt like a lot. Now I seem to have moved on to more specialised search engines. Of course, this might just be a stage. I might go back to using Archivarius much more in the future.