Nothing much has changed. The Xbox One vs PS4 is the same argument as the 360 vs PS3 one. Forty people will be along shortly to justify their own purchases, but the fact is that there’s little to choose between the big 2.
First and foremost, I’d say “do you have any mates with consoles?” Buying into the same ecosystem gives you the option of online play with friends, though if it’s during the day they’d probably have to be unemployed friends.
Second, both have platform-specific titles. This may be relevant if there’s something specific you want to play.
Third, as you’re an ex-360 owner, the Xbox One has (limited but growing) backwards compatibility. If you’ve got any discs from the old console, or downloads associated with your account, you may well be able to play those too. (IIRC the PS4 can emulate the PS2, but can’t play PS3 games.)
Either way, I’d avoid really small hard drives. A typical full-size 360 game download can be 4-5Gb; the same thing on the One can run to 40-50Gb, and even with a disc it’s typically mandatory to install a portion of the game to disk. (The One’s drive isn’t readily upgradable but supports external USB3 drives; the PS4’s is upgradable I think.)