Found on the
Geoweb Guru blog, here is a snippet of the article :
"GIS Cloud has just entered its public beta phase. GIS Cloud is an online "GIS for the web". The 'cloud' in the name refers to it being SaaS (Software-as-a-Service). It is unclear if it is implemented in true 'cloud' fashion (eg. like Amazon EC2 or Microsoft's Azure). Unlike the vast bulk of the "geo-web" systems we cover, this is much more than a simple map viewer/annotator/query engine; but allows more GIS-like data operations. "
Make sure to check the blog for the rest.