I did Digital Media. Lots of students took laptops /ipads into lectures, but most didn't.
Also, as well actually as in lectures, he may want to use a computer in between lectures, when doing group work or just to get stuff done, but without going back to halls. It depends on how he likes to work (and he may not know this himself till starting).
At my uni, on my course you had access to brilliant computers onsite, but people on non-computing courses had to use the "pool" rooms, which had rubbish computers on them IMO.
So, somewhat ironically, being on a computer course at my uni meant I had less need for a computer onsite.
I have no idea what the facilities are like at your DS's uni though! You could ask him to post on www.thestudentroom.co.uk and ask what facilities are like for his school.
If you want to get something for this Xmas, I'd suggest pergaps an ipad or mini-ipad so he can take notes in uni, then sync it with his computer (check he actually wants one!)
Or, ideally, wait till he starts, and buy him a laptop or ipad a few weeks in, as an early xmas present for next year, when he has a better idea of what he needs.