This is why an 8GB iPad Mini will be insufficient
Keep in mind 8GB = ~6.3GB of actual storage
1 solid game w/ app data = 1GB (Metal Storm as an example)
Several photo alumbs and home videos = 1GB
Music albums and Podcasts = 1GB
1 downloaded iTunes HD movie = 2GB
3 magazines in Newstand app = 1GB
50 misc apps w/ app data = 1GB
Realizing Medic311 was correct that 8GB wasn't sufficient...priceless (or hilarious)
If the iPad Mini is designed for consuming written material (as the rumors are swirling about a focus on iBooks), 8GB will be extremely frustrating for many. Newstand chews through storage as Digital Magazines throw in enormous graphics and photos. Ever downloaded an issue of Wired? They are 450MB+ then throw in additional magazines like The Economist and Bloomberg which have audio components which soak up even more storage
I have a 32 GB iPad, and to be honest, my next one will be 16 GB. Yes it's nice to have storage and store my entire music collection on it, but I rarely listen to music on it (I don't workout with my iPad). I also have a few movies there, but constantly use Netflix or ABC player.
I think the number one use of iPad is internet browsing, and that requires a connection, not extra storage.
For the casual user, 8 GB would be sufficient.