To demand stop using concrete is almost as if asking someone to stop eating. There's currently no material able to replace concrete to building necessary infrastructure.
In addition, any other material replacing concrete is likely to contain an even larger carbon footprint per tonne than concrete.
Concrete's CO2 emissions per tonne sit near 100 kg.
That of LVL, MDF, CLT and plywood sits at values larger than 350 kg/t according to the Univeristy of Bath's 'Inventory of Carbon & Energy' www.carbonsolutions.com/resources/ice%20v2.0%20-%20jan%202011.xls.
Furthermore do the most common concrete's of today contain cement supplements such as fly ash and slag, reducing concrete's CO2 footprint substantially.
Canada and the US have commenced using concretes commercially, where CO2 (captured from other industries) is injected and transformed into limestone. www.carboncure.com.
I personally would not want to live in a timber building for health & safety reasons. Timber buildings could burn, rot and are hard to maintain. Sound absorption might be an issue.
Only a concrete building provides that peace of mind I'm looking for in my home.