I've had enough of carrying laptop in a backpack on the bike, but concerned about carrying it in a pannier. Even with padding in a proper briefcase type pannier, surely it'll take quite a bit of vibration? Or am I worrying too much and it'll probably be ok?
Any good/bad experiences?

Get a neoprene sleeve for it to sit in in the pannier and you'll be fine.

I don't think vibration will damage it. I would say you would have to be more worried in case you have a stack. I have a padded laptop sleeve i use.

Bad plan unless you've got a SSD rather than a traditional harddrive. The vibration really won't be fab for them on a regular basis.

The GF has been lugging her laptops around in panniers for about two years now with no ill effects.

I thought all modern laptops had harddrives that secured the disc when shutdown? if your lazy and just put them into sleep mode then you deserve all you get ;0)

Bad plan unless you've got a SSD rather than a traditional harddrive. The vibration really won't be fab for them on a regular basis

Can't see it being an issue for the hard drive unless it was actually on, which wouldn't seem like a good idea anyway.

Cheers – neoprene sleeve sounds like a good idea. Now just got to convince the pannier to fit on my folder…