I was finished my taxes and had a tiny refund, and then found out the online tax software glitched and dropped one of my W-2s (it was while it was calculating my standard deduction, of all things). Since it didn't show me my income until I printed the return, I didn't realize the error. Now I have to file an amended return and will have to cut them a check instead of getting money back.
Technically I will get a big refund and then have to get back most of it, but forms defeat me and this means more forms. Pain in the neck.
Not surprisingly, the call center is bogged down with calls. Could just be panicky last minute filers, but I wonder how many others had this issue?