I vote for NON-hyphenated; but, per DN Journal a couple of weeks ago,
www.Cloud-Computing.de sold for $38,240. Pretty darn good price, especially with the Hyphen AND the "de" TLD.
All of my 49 cloud-related domains are non-hyphenated dot COMs, i.e.,:
Cloud-Related Domains, (Updated as of 9/10/10)
CLOUDUSING.COM
CLOUDCALCULATING.COM
CLOUDCALCULATIONS.COM
CLOUDRESPONSES.COM
CLOUDCOMPUTINGSPEED.COM
CLOUDDOWNLOADING.COM
CLOUDGRIDCOMPUTING.COM
CLOUDSPEEDCOMPUTERS.COM
CLOUDSPEEDCOMPUTING.COM
CLOUDSPEEDDOWNLOADS.COM
CLOUDSPEEDCOMPUTATIONS.COM
FREECLOUDCOMPUTATIONS.COM
CLOUDCOMPUTERSPEED.COM
INTERNETCLOUDUSE.COM
WEBCLOUDUSES.COM
INTERNETCLOUDUSES.COM
FREECLOUDUSE.COM
WEBCLOUDUSE.COM
PRIVATECLOUDPROCESSING.COM
PRIVATECLOUDSCOMPUTING.COM
FREECLOUDPROCESSING.COM
CLOUDPROCESSINGDATA.COM
DATACLOUDPROCESSING.COM
FREECLOUDUSAGE.COM
ACCOUNTINGCLOUDS.COM
RESEARCHDATACLOUD.COM
DEFENSECONTRACTORCLOUD.COM
CONTRACTCLOUDS.COM
VENDORCLOUDS.COM
CLOUDBUSINESSPROCESSING.COM
FREEBUSINESSCLOUD.COM
BUSINESSCLOUDUSEAGE.COM
CLOUDBUSINESSUSE.COM
BUSINESSCLOUDUSE.COM
MEDICALCLOUDUSE.COM
LAWENFORCEMENTCLOUD.COM
TRAVELCLOUDUSE.COM
MEETINGCLOUDUSE.COM
SEARCHENGINECLOUD.COM
INFORMATIONCLOUDUSE.COM
CLOUDCOMPUTINGUSE.COM
FREECLOUDCOMPUTINGUSE.COM
FREECLOUDUSING.COM
CLOUDUPLOADING.COM
DOWNLOADINGCLOUD.COM
CLOUDMOBILEDOWNLOAD.COM
MOBILECLOUDDOWNLOAD.COM
DOWNLOADINGCLOUDS.COM
UPLOADINGCLOUDS.COM