My personal opinion.
I hybridise things, pirate copies tend to avoid all the crap that comes with (read up on starforce and the like as well as other checks on things like disc drive emulators) games, tend to have a small footprint when it comes to space used (either pre install or post) and much more.
Official copies make life a little bit easier when it comes to online stuff if you want to go that route and often they come with extras that can be fun to toy with (a lot of groups leave these but not always).
With regards to updates it is usually the dox division of a group that handles such things and it is easy enough in most cases to update.
Also do not listen to anyone that says steam is hard to pirate, in all my experience steam has made things so that they have never been easier to pirate by using a generic protection.
With regards to online multiplayer there are two main ways around it (assuming you can not find a serial). Also there are plenty of free online games (there was a thread around here somewhere, probably a sticky).
Those ways around it are cracked servers and VPN/similar.
I prefer these as the additional technical hurdle prevents most of the idiots from playing and hacked servers also usually have a "fun mode" where some of the grind/restrictions of the original are removed. Do not get me wrong some go completely overboard but many strike a very good balance.
VPN (virtual private networking) relies on internal network play and uses a virtual private network to allow others to join your network and thus play with you. Some use simplified tools like hamatchi and others use more complex (but more configurable) tools to set up a VPN.
On the subject of "why PC multiplayer when there is a [insert home console]" assuming you do not mind paying for live on the 360 then I say mods for games. It takes a few months on average for them to get going but once they hit then that is why you want a PC to play online with. Good news is that PC games very rarely hold their price for long and by the time decent mods appear you can usually pick up a game for lunch money and the hardware required*
Controllers are easy enough to rig up to a PC and have been for some time now, keyboard and mouse are a damn good control method for most games though and with most games released in the last 10 years able to simultaneously support controller and keyboard or dual input of some form you are laughing.
*PC games have somewhat stagnated recently as DX10 has failed to impress most people and most games will run on older hardware (I am quite happily playing the latest and greatest on my 7900GS) either out of the box or with some fiddling (
http://www.widescreengamingforum.com/wiki/...x.php/Main_Page and
http://www.tweakguides.com/ ).