[alister]

I do know how to turn off Spotlight, but thank you.

My broader point is that it is becoming impossible to truly delete a file or maintain separation between different parts of your data unless you are very technical and meticulous.

How many other features are there in OS X like Spotlight or Versions that we need to be aware of?

The OS should be designed so that we don't need to be constantly on guard for these privacy gotchas.

[ZoFreX]

I would argue that disabling Spotlight indexing for a particular folder isn't that technical, the UI for it is very simple. Of course, realising that you should do this perhaps requires a more technical mind! Overall though the point remains (swap, SSDs, etc), and is quite scary.

[earl]

I misunderstood. In that case, yes, I totally agree. I'd suggest whole disk encryption but users will hate it, since if they forget their password the data is really gone. For reals.