Anyone got an updated list of things you'll need to install the game?

and do you need a constant internet connection to play?

I haven't seen anything official yet, but this is what I  have read:

The game will have a very low form of DRM protection in which:

In order to install the game, “you need to connect once to install the game,” StarCraft II lead designer Browder revealed. A player will also either have or sign up for a Battle.net account during the installation process.

http://www.gossipgamers.com/starcraft-2-getting-drm-protection/

You will be able to install it as many times as you want.

StarCraft 2 is heavily loaded with DRM (Digital Rights Management). It is a system designed to validate and allow functionality only to legal software. Let me explain how it works in this specific case:

1- Installation: You will need internet connection prior to proceed installation of the game. The DRM connects to battlenet and verifies date, if it is past launch date it will allow you to install the game, downloading data allowing decription of the content burned into DVD. You have the option to register your cdkey to one existing bnet account or create a new one.

2- Multiplayer: Only when connected to the internet. All game data travels through "Player1 pc" > blizzard server > "Player2 pc" even if you two are connected through LAN. If battlenet server goes down you cant play.

3- Map creation: Map creator can only build and test maps when connected to battenet.

* you will be able to play SP as a guest, of course after going through the first step of the DRM.

As you can see, the game is nearly unplayable if your internet or battlenet servers goes down.

(*everything described is probably innacurate, just speculation on things I have seen on these forums or statements by mods.)

http://forums.battle.net/thread.html?topicId=25969020561&sid=3000

Does anyone know if I can play with my brother with only one copy of the game?

Most definitely not. You need 2 for Battle.net and there is no LAN.

what vlad said is right. There is no option to install spawn copies for LAN this time around which is unfortunate but predictable.

wait wait, am i going to be able to play offline mode if i don't want to play online? if i just wanna go single player? do i still have to be connected to the internet?

Can't answer that. There was an offline button when my internet was down, however that may or it may not allow you to play single-player online.

you'll have to activate your copy online in any case. but it has been confirmed, though a while ago, that after that you can play the whole single player offline. anything that has to do with multiplayer -> connected to battle.net

I'm surprised the DRM of starcraft hasn't created any stires, it is imo far worse then spore.

One player account per copy of the game is rubbish, I bought my copie, however my brother was given first go. Now I am unable to even play the game I bought with my own account. Can't play single player even.

I could understand only allowing one copy of the game to be played at a time, but not a single person able to play per game bought. I'd have to buy 4 copies. >.>

Atlest this has warned me not to bother buying anything from blizzard again.