[delan-temp]

I've searched thoroughly, and have not found any emails, but I do of course receive emails fine from the @ycombinator.com address of the staff member I spoke to. I'll try redoing the test with a different email provider though.

[moontear]

This is something I believe you should have done in the first place. You write that your e-mail setup must not be wrong as you are using Google Apps for your domain- but in the end exactly that might be the problem (wherever it stems from).

[molmalo]

Check if you have an automated filter/rule in your gmail account that could be deleting the mail as it arrives.

[delan-temp]

Yep, the filter list in Gmail's settings is empty.