PS4 owners will need to download a day one update in order to unlock many crucial features, including online multiplayer. You can save yourself some time on launch day by downloading patch 1.5 now.
In order to get the patch in advance, all you need is an Internet-capable computer and a USB storage device with about 1GB of free space. Create a folder on the USB drive called "PS4," and then another folder inside it called "UPDATE." Then download the file (PS4UPDATE.PUP) into the "UPDATE" folder on the drive.
Once you've got your new PS4, hook up the USB drive to it while the console is off. You can then power up the PS4 in safe mode by holding the power button at least 7 seconds. When the console starts up, select [Update System Software] from the menu and follow the prompts to finish updating to 1.5.
Multiplayer is only one of many features included in patch 1.5. After the update is applied to the console, players will have access to Remote Play for Vita as well as second-screen features for Vita and mobile devices. The patch also unlocks several social features, including party voice chat, recording and sharing videos and images, Ustream and Twitch support, and multiple log-ins. Quality-of-life features like being able to download games while playing or stream music are likewise restricted until you download patch 1.5. You can't even play Blu-ray or DVD discs without the update.
Sony says that you can download this patch in the background while you play. For example, you could putz around with Killzone: Shadow Fall's campaign until 1.5 is downloaded and then dive into the online features. Still, I suspect there's a lot of people out there who just want to play online. I mean, shit, who wants to play the campaign of Call of Duty: Ghosts? Not me. Pre-loading the update onto a USB drive is the best move if you want to deathmatch right away.
In fact, regardless of what you plan to do with your PS4 on day one, you should download the patch beforehand. If the launches of Diablo 3, GTA Online and SimCity have taught us anything, it's that online launches have a high potential for sucking. Servers inevitably get overwhelmed, users get weird error messages, and everyone heads to the forums to curse the developers' good names. Do you really want to spend your first day with your new console staring at a progress bar or complaining on forums? Save yourself the headache and download the files before Friday.