The question is quite simple, do you have dualboot?
If yes, post which systems are you dualbooting, for example :

I am dualbooting Windows 7 and Windows 8 RP w/ WMC

Yes.

On my main (laptop): Windows 7 HP and Windows 8 RP (with WMC) (Windows 8 is on vhd)
On my netbook: Windows 8 CP and Windows 7 Standard

Once 8 comes out I'll install it on my main without dualboot.
Not sure if I'll buy 8 for my netbook-since its a bit old, but if I do, I'll prob dualboot it with Ubuntu (but not sure if I need ubuntu, since Windows 8 is quite fast, on the other hand the start sceen will be annoying since Metro doesn't work with small screens).

Windows Vista and Ubuntu 12.04. Both x64.

Vista?

Which one do you use more?

I use both indifferently.

windows Vista home premium 64, windows 7 home premium 64, I mostly use vista for browsing and gaming because 7 came preloaded on the pc with a lot of bloatware,so vistas a lot faster and boots faster too,but 7 has my serious programmes like office and photoshop.

You downgraded from Windows 7 to Vista due to Bloatware? And then installed Office+Photoshop on the least used OS?

I have triple-boot.

Main partition: Windows 7 Ultimate x64
Secondary partition: Windows 8 RTM x64 with Media Center
Tertiary partition: Ubuntu 12.04 w/ custom desktop and repositories.

Yes, I have.
openSUSE (replaced it) Ubuntu and NetBSD

Yes. I've got Windows 7 Ultimate x86 in my primary partition and it's my main os, got office installed on it, some games, various programs etc... and in a secondary partition i've installed Windows 8 Pro RTM x86 just for testing it, but i'm thinking of removing it since the metro ui theme gives me an headache (i also thought that it was done better, the RTM of Win 8 looks made really fast leaving also some small graphics bugs :-/ , plus the metro ui start screen is totally unuseful in my laptop ) .I prefer sticking with 7 because it has got gadgets and the good old microsoft games and better customization and better compatibility, although Win 8 is a bit faster than 7

Yes...
Windows 7 Home Premium and PCLinuxOS 2011.11, both x86

Windows 7 + Windows 8.

At the minute I do, although on 2 different HDDs, but only because I thought I would be wiping Win 8 after a while but its growing on me

I used to dual boot Windows XP with Windows 7, but then my XP OS got so outdated (I used windows 7 instead), I scrapped it entirely after I reinstalled my computer.

So no, I don't dual boot. I was thinking of getting Ubuntu on my secondary hdd, but I found out that the disk speed wasn't fit for that kinda thing. :/

Primary comp: Win7 SP1 and Win8 RTM
Game server: Windows 2000 Server and later Win98
Secondary comp: Win95 amd WinNT4

No. I have a quintuple boot.

XP Sp3/7 SP1
I have XP as a rescue OS when something is going bad with 7, I rarely use it. I will skip 8 just as I did with Vista.

Cool, but you forgot to list the OSs.

I was thinking about putting Ubuntu 12.10 as my third-but you can't boot Ubuntu off VHD, and Ubuntu and Windows don't mix too well (although I suppose GRUB works OK). It might be fun to use though, so maybe...

Do a Wubi install. Your Ubuntu partition will be limited to 30 GB, but you'll be able to easily access and use all your Windows files.

True, and I do recommend Wubi for those who primarily use Windows. But sometimes, you might get slow file transfer speeds while using a Wubi Ubuntu installation. At least I had that.

Yeah, I had that too on occasion. Dunno why.

I have five-level-boot at the moment with the following operating systems:

1. Lion Developer Preview 1
2. Lion RTM
3. Mountain Lion Developer Preview 4
4. Windows 8 Consumer Preview x86
5. Windows 7 x64

But soon I'm planning to move to four-level-boot:

1. Lion Developer Preview 1
2. Mountain Lion RTM
3. Windows 8 RTM x86
4. Windows 7 Service Pack 1 x64

Thanks for the tip, I'll look into that. (and I probably wouldn't go over 30GB for Ubuntu anyway-just use external drive for any large files).

Laptop (Soon to have):
- Windows 7 Ultimate SP1 x64
- Windows 8 Pro w/ Media Center SP0 x64

Desktop (It's bloated with lots of files):
- Windows XP Professional SP3 x86
- Windows 7 Ultimate SP1 x86
- Windows 7 Ultimate SP1 x64
- (Soon) Windows 8 Pro SP0 x86 (my dad thinks a x64 upgrade is very risky)

2 – Laptops, 2 - Tablets & 1 - Server = No
3 - Desktops = yes
Main Rig = 6 OS’s, Test Rig #1 below, Test Rig #2 - 5 OS’s (only one incl. XP on it).

Test Rig #1
Vista x86
Windows 7 Ult x86
Windows 7 Ult x64
Windows 7 Ult x86 – Test
Windows 7 Ult x64 – Test
Windows 7 Professional x86
Windows 8 Enterprise x64 – RTM
Windows 8 Professional – x64 RTM