Dave,
I think your question has perhaps two answers - 1. What specific arguments for/against a one-man-adam are there? and 2. (sociologically speaking) how do we integrate scientists into the church?
1. I'm not a biblical languages scholar but from what I have read it is uncertain how to translate the hebrew word man that is used in Gen.
The interpretation of the word adam (and I think adamah) is pretty tricky. adamah means ground or dirt and adam can be translated a man or mankind. The point of the poetry in
Gen. 1 is that "man" (probably mankind) was created from the dirt. The life came from stuff. This is also scientifically true (our carbon atoms are the same as those in the ground) but it took until the 1700 and 1800s to undo the thought that life was made from a different material than ordinary matter. The church (and philosophers) could not conceive of life not being a special and separate thing and therefore twisted scripture.
The other important issue is one of contemporaneous witnesses - when was the story of creation actually written down. How many times was it passed down orally before it was written? Did anyone have a scientific or historical recording of how many people existed at the various times in Gen.? Since I don't ever read in scripture that it was dictated by someone who was there with a complete definition of terms (like how long is a year?), I think the gist of the story of mankind is presented with a particular focus on the nation of Israel.
Gen 1 is a particularly poetic view of origins that distinguishes itself from other recordings of creation and even today distinguishes itself from a purely rational and observation-based view of evolution. The trustworthiness of Gen stands in spite of its lack of scientific and historic detail.
Paul's statement that "since sin came through one man, it was necessary that sin be eliminated by one man" (lots of license with this paraphrase since I don't have time to look it up

) does not require a literal one-man-adam. I can easily understand that in a figurative, yet very real way. I have never met anyone who does not have "adam's" sin problem. In that sense, we are all united as one - we are all sinners.
2. We scientists are not trying to make peace with scientific discovery. For a scientist who is a christian, every aspect of our lives needs to be truthful. When we record an observation, we do not have the luxury to "disbelieve" it. When we read a paper from another scientist that records a discovery that seems hard to believe, we look for additional confirmation or solid evidence to the contrary.
Many of us are looking for peaceful coexistence with our church who often labels us as heretics or tools of the devil or any number of additional derogatory phrases. If you read the christianity today article you will notice how many professors are losing their jobs for helping students and the church to understand and integrate scientific facts and theories with the equally important task of worshiping God and living a holy life. I have been a Nazarene since birth, but have often heard the phrase "those scientists" and then some derogatory and inflammatory comment follows. I simply will not debate these statements with people who start out on the attack. Underlying these statements I have found that these individuals are expressing habitual anger. They say things like this about scientists, politicians, friends, family,... you name it. These folk need to be confronted with their sin.
There are others who are asking honest questions. So I would ask that if you find someone who is honestly struggling with science and faith to ask them to come to peace with scientists not with science - to become reconciled with their fellow believers. (This could also be said to the scientists as well). No one's mind needs to be changed. The right ideas do not make a person a part of the Kingdom, however, unrighteous behavior prevents a person from continuing as a part of the kingdom. The ways in which we argue and debate are more important than the outcome.
I went to ENC 30 years ago. The science departments were excellent training grounds for scientists. The professors were also excellent examples of holy, love-filled, Spirit-filled living. I am sure the same could be said about all of our colleges then and now. Large proportions of our science graduates stay in the church long after graduation. From what I can tell, each of our colleges is attempting to prepare students for the reality of the scientific endeavor and a faithful christian walk. The books and discussions from Giberson, Collins, et al are having a positive result for those of us in the scientific community. Students are better prepared to live in a world where they can have their science and their faith and not just one or the other.
Doug