What sort of tasks would we be working on as part of the Software Engineering Scheme?

It will vary depending what team you are in. I am a placement student and have been put in the tablets and devices team. Most of my tasks centre around adding features to the app my team created, fixing bugs or completing spikes (small investigatory pieces of code to prove if something is possible).

Do previous skills have an effect on team placement or is it random?

I can't answer with 100% certainty but I imagine that your skill set and personality will be taken into account when choosing what team to put you in but it will also be partly down to availability (e.g. which teams want another member). Also with the grad scheme, they'll want to put you in different teams throughout to see where your strengths lie

Cool, sounds exciting, thanks for the response!