I doubt Bill Gates would use Bill on his CV. It would be William. Bill Gates isn't the best example though as he probably doesn't need a CV at this point of his life. I bet he used his full formal name when he was applying to Harvard though.
I was trying to make the point that a CV as incredible as Bill Gates could be discarded if a company is going to be put off simply by how a first name is spelt (from what you were saying). It was meant to be a lighthearted example, nobody needs to get carried away and start researching his application forms
As I have now said on several occasions, we are not looking for an alternative to Joey, but thanks for your suggestions anyway. Some are quite comical.
One thing I am slightly put out by is the suggestion that they are 'really can't be arsed' names. I have been with my partner for 6 years and we have thrown names back and forth when discussing babies for this period of time. We have bought baby names books and I have made list upon list, narrowing down, starting again...etc etc. I never thought we'd agree as I've always loved traditional names, whereas he likes what I call American, or tacky ones.
I was so chuffed that we'd finally reached a decision that I felt compelled to make this post. I'm surprised a name like Joey could spark such a debate, but on the positive side it's confirmed to me that I love the names so much that not even some of the negative comments have put me off. 
I've worked with children for 4 years and trust me, there are far more obscure and zany names than Joey! Although initially your reaction to a 'different' name is 'Oh'
, you quickly become used to the name and couldn't imagine it being called anything else. As already mentioned, Joe is the back up, or more 'adult' name he will have to choose from if he wishes, although I'm sure by that stage in his life he and everyone around him will be accustomed to his real name 
I am genuinely surprised by some of the archaic views on here regarding CVs still. I think we'll just have to agree to disagree on that one, I just hope that when our child is applying for work the establishment is credible enough to be open-minded to his name. Who knows, it may even help him stand out against piles of 'Davids' and 'Williams' 
Thankyou to everyone who has responded positively (whether you like the names or not). We are so excited! 