Will I get questioned about my personal statement at an Oxford interview?

It is very likely that you will. (But it is also possible that your admissions tutors will make no mention of it at all, and even that they won't have read it.)

The two principal ways in which your PS will be used are:

1. To ask you about something non-academic or extra-curricular as a way of breaking the ice or just because they're genuinely interested in what you get up to.

2. To challenge you on an interesting view you express, or get you to expand on a claim you make. Therefore: (i) make sure you have read and have interesting things to say about any books or other reading you mention, and (ii) make sure you can back up any views you express or claims you make with further argument.

Why, are you planning on lying in it?

You should be prepared to discuss anything that's in it.

Not at all, there are points which are true but I would find difficult to discuss.

Hmm I see. Is this also true for maths? I've heard they don't even read maths personal statements?!

Then why include them? Can you give an example? You're being very cryptic - if we knew what you were trying to get at it would be easier to give an answer.

Well that's simply because of the warnings I've read about sharing personal statements online : P

In the PS I've mentioned a talk about higher dimensional surfaces, I really enjoyed the talk but I've not found researching the topic as interesting as other areas in maths so I'm not sure whether or not to mention the talk.

Fair enough, no-one's expecting you to post anything you've written!

You could say something like 'My main interests lie in x, y and z, though I found a recent talk on higher dimensional surfaces by Professor xxx which I attended at the University of yyy very enjoyable and interesting...'

Any information appreciated.

Well I've made a bit of a claim following it, I could PM you the part if that's ok with you?