Paramount usually does everything on an individual basis, but sometimes the new concept rides(Stealth, HXLC) come from the central team and they pretty much ask the parks if they would like one of these concepts. Paramount is known as one of the biggest companies for prototypes, firsts, and record breakers such as the suspended, TA2K, flying, shuttle loop, stand-up looper, only looping woodie, etc.
I know that PKI makes their decisions by adding up all surveys(which not much of the public have heard of B&M), traveling to other parks and seeing ride popularity, and most of all what can really attract and crowd, but still bring an ROI which PKI has always had much success in doing especially in '99 and '01 looks promising as well. The surveys are not only opinionated, but they also take stats each year of how many men, women, teens, children, come in which helps them decide on which level the attraction should be on. 2001 has something for everyone: kids and family-Nick Central expansion; family and teens-7th Portal; Teens and adults(return visits)-Flight of Fear lap bars(larger audience).
Surveys are usually done very early and very late in the season. Very early helps them see how their new additions turned out and they pretty much just want to know how they're doing. If you really want that B&M, catch a surveyor late in the season...but if that is decided upon, you won't see it for 2-3 years depending on design and research. That's pretty much all I know behind the scenes at PKI. I wish someone would tell me what the 2002 attraction is, but all I hear is "I don't know", "I can't tell", and "Something BIG". So, we'll just have to see.
If you want to know why there wasn't a major coaster in '01, most of the people that visit a park are either family or are going to come whether something new is there or not. And SOB made an underwhelming mark on their attendance. First year out of several, they lost the attendance wars of Ohio to CP.
As far as I know, this is what has and should continue to go on. I worked there last year and am good friends with a guy at guest services who "swears" we'll get a "water coaster" next year. Hmmm, we'll have to wait and see. BIG usually doesn't fit as a description of a water coaster though. :(
