NC previously said they would also be ready on January 31, 2014. Announcement here.
Now the tax software companies will have to rush to do final testing before all forms can be filed through them. People filing now probably will not run into a problem but those with a complicated situation may have to wait for final IRS and state approval of some of their forms.
Even if you electronically file and owe tax, you can still wait to pay until April 15, 2014. You can either ask IRS to draft the tax on a certain day or mail a check along with a coupon on or before April 15, 2014.
You can find the details in IRS Information Release 2014-9