Well, I wouldn't get too carried away with those equal signs. I suspect that IHG has Marriott on sheer numbers mostly in the lower-end brands.

My thoughts on quality...

Ritz = No IHG comparison.
JW = IC. Roughly...I consider both good brands but there's that whole RA status you need to have for IC. "Regular" MR Platinum works at non-resort JW's.
Marriott >>> Crowne Plaza. This one isn't even close.
Renaissance >>> Indigo. This one isn't close either.
CY < HI. This one is all over the board but I'll give HI the edge here from the perspective of a Platinum in both programs.
FFI < HIX. My few 2011 HIX stays were in newer builds - pretty good stays.
RI > Staybridge. RI gets the edge both on quality of the newer builds and the fact that they have some interesting/character properties. That said, there are also some tired suburban properties that need a retrofit.
SHS/TPS > Candlewood. Both of those brands are somewhat nicer than Candlewood IMHO.

To me, it's pretty clear cut: PC/IHG is a solid program if you do a ton of rural stays for work and then redeem awards at IC. Being able to stack promos and pile up big points is a major plus. The availability and quality of the motels - especially the newer HIX's - is a marked advantage over most Fairfield Inns. At least now, in 2012...

But if you need either long-stay or regular city business hotels, I think Marriott is a far better program overall. Every Crowne Plaza I've stayed in in the past 10 years feels closer to Ramada than Marriott.

Hasn't IHG talked a long time about pumping serious money into a revitalization of the CP brand? If they want to be thought of alongside SPG, HH, MR, and HY, I think they have to do that. There aren't enough IC's in this world for them to rest on that brand alone.