BioShock is a shooter unlike any you've ever played, loaded with weapons and tactics never seen. You'll have a complete arsenal at your disposal from simple revolvers to grenade launchers and chemical throwers, but you'll also be forced to genetically modify your DNA to create an even more deadly weapon: you. Injectable plasmids give you super human powers: blast electrical currents into water to electrocute multiple enemies, or freeze them solid and obliterate them with the swing of a wrench.
Bioshock had serious mouse issues, called mouse acceleration that could not be turned off, it took just over 3 months after the games release before they patched it... controls and UI are still 2 causes for concern.
They delivered on the UI... mostly.
The game lacked an inventory (it did have a weapons/plasmids screen, but that only served as a quick way to see what weapons and plasmids you have)... you could still carry all the weapons you find without having to discard one and each time you tried to pick up some food you would automatically scarf it down like a hobo.
It also lacked a screen to show you how much 'components' you've found.. you had to go to a friggin workstation just to see what you've found.
It also suffered from being to easy due to the vitachambers not requiring to be activated or having any penalty for being used. And lots of ammo, health, eve but barely any grenades. Either way it could have had more PC focus.
It did some things well, like allowing the introduction to Bioshock being player controlled rather than just being a long cinematic cutscene. Eventhough we don't get to do much during it, it still added so much to the game. Using gameplay instead of a cutscene is almost always a better choice and here its shows how well it can be done.
The game has other good things about it but all the rest it merely copy pasted from System Shock 2, without being nearly as scary.
The main character has the same role, to be a betrayal/plot twist later on but your only friend at first, hybrids are splicers, psionics are plasmids, and your melee weapon is still a wrench... The game could have been more original.
Innovation is something I value, hence the lower score I gave it.
Bioshock got a lot of praise for being fresh just by changing the setting to something unique. It takes more than that to make a great game.
The Big Daddy fights where quite fun and challenging though which are one of its saving graces.