We'd have slow ass notebooks with no Windows compatibility.
I was at WWDC 2006. The Pentium 4's were so much faster than the G5s it was shocking. The sense was that Apple had pulled the wool over everyone's eyes when it came to PowerPC vs. Intel. It was hard not to feel like Apple had been lying about PowerPC vs. Intel for the few years before.
Also stop comparing the Power7. They're not at all PowerPCs. They require giant, giant boxes and huge power supplies. It's like comparing a dump truck to a F-150. Yeah, you can haul more, but it's not something you'd actually ever regularly drive. The Power series also existed alongside the PowerPC and they were always significantly faster than the PowerPCs, so it's not and accurate comparison.
(Power7s are also $10,000. So you're talking about a Power Mac that would be $10,000. You could easily buy several Xeons for that price.)
Macs were always behind the times they didnt get USB 2.0 for YEARS after PCs got USB 2.0 Windows has had USB 2.0 Support since Windows 98SE! Mac did not exceed the 1GHz threshold until well after Windows PCs had over 1GHz Macs did no exceed 2GHz until the G5 PCs at the time of the last G5 windows had alreaday passed the 3GHz mark not to mention that Apple didnt have 64bit til what Lion? while PCs had 64bit support since late 2005