Question: I am hoping someone can explain in simple terms, what it really means that windows XP will be [end of life](http://windows.microsoft.com/en-us/windows/products/lifecycle)?

It looks like SP2 is already not being patched, but maybe SP3 is going to be patched up until 4/18/2014?

So I assume that means there will be windows update patches available until that date?

What happens after that, no patches at all?

That means the potential for hacks, virus, etc. are greatly increased?

Answer: 
Simply put EOL means no patches no support. From <http://support.microsoft.com/lifecycle/?LN=en-gb&C2=1173> "Support ends 24 months after the next service pack releases or at the end of the product's support lifecycle, whichever comes first. For more information, please see the service pack policy..."

For service packs:

"Security updates released with bulletins from the Microsoft Security Response Center will be reviewed and built for the supported service packs only. Daylight Savings Time and Time Zone updates are built for fully supported service packs only."

XP SP2 is EOL

XP SP3 has a supported end date of 4/21/2010 that is when mainstream support ended. XP is in the extended support phase, so only security fixes will be available until 2014 (if I read the chart correctly). As always it's best to get information like this from the vendor.

As far as impact, it's a cost to upgrade so businesses need to evaluate whether or not to upgrade. Many companies have realized that newer machines come with win 7 licenses so there is no upgrade price.
Just some further information, many vendors only provide support for their products when they are used in a supported environment. For example JoeAccounting is the software your accounting department uses on their Windows XP computers. Say something happens and you have to re-install JoeAccounting on their computers, but you run into an issue. Right now you can call JoeAccounting support and they can help you solve the problem, in a few days from now if their policy is to only support their product on operating systems that are in support from their own vendor, then they will not be able to help you with the issue.

Many vendors utilize this policy and for good reason. If the source of the issue is something with the operating system itself, the vendor can work with the OS vendor to resolve the issue. If the OS isn't supported they can't do that.

If you are still running XP machines its not too late to upgrade, but to be honest even though the out of pocket is less to just buy Windows 7 and install it on the XP computers, it is better in the long run to buy new computers, a $1000 computer would pay itself off with increased productivity and decreased support cost in a year. Its very important even for small businesses to have life cycle's on their IT hardware and software. If you still have XP machines odds are they are 4 or more years old and that old in the business world for a computer.