I went to Ixtapa in 1987. I LOVED it! My VERY favorite place in Mexico.
I've also been to Cancun, Cazumel, Matzatlan, Puerto Vallarta, Cabo, and the usual places up and down the coast (Rosarito, Ensenada, San Felipe, of course passing thru TJ) So from these my favorite was Ixtapa. The water wasn't as pretty as in Cancun/Cazumel, but it was lush and the water was like stepping into a warm bath. Since the weather has changed a lot, all over the place, it MIGHT not be like it used to be...and of course I'm sure it's a lot more commercialized. There were huge hotels going in while I was there. But as of now, it's still my favorite place in Mexico.
PS Thanks for your post, I'll go check our your link!