This is our first year hosting, and our 1099K is incorrect as well. The amounts do not match the Airbnb earnings reports or the transactional guest history.
I'm an accountant and I was a tax preparer for years, so I know the Airbnb form is wrong. My discrepancy was rather minor, but I'd hate to see how bad things could be after a full year of hosting.
Someone at Airbnb really needs to address this issue. It appears to be a long-standing problem that they are failing to resolve.
And for those of you not in the US, the IRS is looking at our tax returns to verify that we're reporting all income. If Airbnb reports a higher number than was actually earned, and we fail to gross up to that number, we'll get a 'matching' notice and the IRS will assess additional taxes on the shortfall.