http://www.salon.com/2012/08/03/10_theories_on_romneys_taxes_salpart/
1. Mormon Tithes
2. Things That Might Infuriate the Base
3. Harry Reid, Lazy Blogger (he paid no taxes for 10 years)
4. It’s the IRAs
5. The Mini-Mitts (trusts for his kids)
6. Is It All About 2009? (paid no taxes?)
7. CEO, President and Chairman of Bain
8. Is Mitt a Felon?
9. Are There Other Non-Disclosures?
10. There’s Nothing – It’s Just His Sense of Entitlement
My guess is it's #7. He's been lying about his Bain record and his tax returns will reveal the truth. His business experience is his admitted primary qualification for being president but he doesn't want to be held accountable for what Bain did post '99 when he supposidly left to run the Olympics. We know he was listed as CEO after that but his tax records will show he profited from Bain's destroying companies and outsourcing jobs overseas.