Your business may use Internet Explorer because the company email or company website services only work with Internet Explorer. That is perfectly fine to use Internet Explorer for those reasons. But, what you can do is use another web browser to actually surf the internet.
What did the flaw do? The security flaw which was discovered by computer security company FireEye observed a cyber criminal group launching "spearfishing attacks" on some of their customers. Someone within the targeted company would get an email with a link to the website the cyber criminals controlled. Once the victim would click on the link while using Internet Explorer, their system would be compromised. These attacks appear to be motivated by industrial espionage targeting intellectual property or corporate secrets. The cyber criminals didn't seem interested in regular consumer data.
Now that the code which was used to exploit Internet Explorer is known, it doesn't mean that another cyber criminal organization won't use the code as well.
But now that Microsoft released the fix which came out on May 1st 2014, you should be patched up against this threat. The good news is Microsoft fixed the issue. Just make sure that your Windows system is updated. Our Ohana that subscribes to our maintenance service should be a ok. :-)