Yes, in fact, if your MAGI is $220K or over as a couple, you are not able to open the account. Having a relative with lower income is a good way to set one up.
As MrChrister commented, the Coverdell is more limited, only $2000/yr, dropping to $500 if congress doesn't act. (limit was $2000 in 2012, to clarify) Funds must be disbursed by age 30 to the ...
This is a partial answer.
Coverdell ESA must be withdrawn when the beneficiary turns 30. The 529 has no such age restriction. A decent comparison is at Coverdell Education Savings Accounts a wiki entry at the Bogleheads site.
To add another point, the Coverdell limit is $2000 per year deposit, the 529 is subject only to the rules of gift taxation, so a ...
You can roll a Coverdell ESA into a 529, but you cannot go the other way around.
529's have contribution limits an order of magnitude higher than that of a Coverdell ESA. If you could roll a 529 into a Coverdell, it would defeat the purpose of the limit on the ESA.
Not sure how authoritative it is, but according to this site, yes:
Can a corporation, partnership or other non-living entity make the contribution to an ESA?
Yes. The tax law does not restrict the ability to make contributions to living individuals. Corporations and other entities may make contributions without regard for the usual donor income limit....
From the IRS Pub 970
Any amount distributed from a Coverdell ESA isn't taxable if it is
rolled over to another Coverdell ESA for the benefit of the same
beneficiary or a member of the beneficiary's family (including the
beneficiary's spouse) who is under age 30. This age limitation doesn't
apply if the new beneficiary is a special needs ...
I wouldn't be surprised if it was similar to excess contributions. The fairmark.com article More on Contributions to
Coverdell Accounts suggests,
"Unless there is a timely corrective distribution, a 6% penalty tax applies to the excess contribution. What's more, the 6% penalty applies to the same excess every year until it's withdrawn from the Coverdell ...