I'm not so sure it's a good idea for self pubbing authors. Let's run the numbers.
You self pubbed a book and you're selling the both the Kindle ebook and the Createspace paperback on Amazon.
The ebook sells for $2.99 and Amazon pays you a royalty of $2.04 for each book sold.
The production cost for your paperback is $3.03 and you priced your paperback at Createspace for $6.99. Amazon sells it for $6.29 but that's OK because Amazon still pays the royalty based on the $6.99 price. You earn $1.16 for each paperback sold. (Actually, one of my $6.99 books pays $1.16. The other one pays me only 90¢)
Enter the MatchBook - To join, I need to meet two conditions:
1) My MatchBook Promotional List Price must be at least 50% lower than the regular Digital List Price
2) I can only choose between the following prices: $2.99, $1.99, $0.99, or free
Since neither $2.99 nor $1.99 is a 50% reduction of my regular Digital List Price ($2.99/2=$1.495) I must choose either 99¢ or free.
If someone buys the paperback for $6.29 and gets the ebook free:
I earn $1.16 and lose an ebook sale that would have earned me $2.04. I'm down 88¢ and the buyer can pass the paperback around to friends. They could share the ebook too but that's not as easy or as common.
If someone buys the paperback for $6.29 and gets the ebook for 99¢:
I earn $1.16 on the ebook and either a 35% or a 70% royalty on 99¢ (I'm not sure which royalty rate Amazon will use. I'm waiting for a reply to my email.) So if Amazon pays 70%, I earn 69¢ (35% pays 35¢). This leaves me either $1.85 ($1.16 + .69) or $1.51($1.16 + .35) Either way, that's less than just selling the ebook and earning $2.04.
On the other hand, if I don't participate in the Matchbook, I'll earn $2.04 on each ebook sale and I still have the potential for a paperback sale.
I don't see any indication that failing to participate in the MatchBook program will hurt my paperback sales. I also don't see that it will increase my ebook sales.
I'm inclined to let this program pass without my participation. Anybody have any opposing points I should consider?