People usually go with 8GB - not sure why. I'm assuming they believe 16GB is too high and won't be needed so they don't spend the extra money. Sometimes, 8GB to 16GB is equivalent to buying 1TB for $59 or 2TB for $69. There usually isn't a huge price gap between the two. I bought a 16GB kit for about $80 on Newegg. The price went up to $140. I told G.Skill I wanted to swap because it didn't work. I swapped it with $80 8GB kit.
Personally, I have 8GB for my laptop (highest is 8GB, but people get 16GB but I couldn't get it to work) and my three servers that house Active Directory, DNS, DHCP, and backup each have 16GB.
8GB is good, it's okay and I think you'd be alright. But if you have many many things open and you want to be safe, I'd suggest higher. Windows 8 is good with RAM. I usually have tons of tabs open, remote desktop, vSphere Client, outlook, Skype and Spotify and only takes over half. Right now, I have five tabs, outlook, and Skype at 3.5GB out of 7.4GB (8GB total, but 7.4 usable - onboard GPU).
For a brief answer -- if you are editing videos or such, I'd suggest 16GB so then you have safe room and can even create a RAM disk. 8GB minimum.
