My personal two cents: I think that marketing something to the Open Source Harware community and forcing them to use a public cloud for it isn't really that big of an issue, is it?
The only big risk is CircuitMaker being scrapped and all desings lost, that would suck indeed, but then, who guarantees the survival of your harddrive? Ever lost a file because your drive hiccupped or failed? I know I have, and it's happened more than once. Now I backup regularily on a RAID5-Array on my NAS, but from what I can tell not many people do(and I myself tend to forget for weeks so there's still that risk...). If you work on your Laptop somwhere on a trip you run the risk of it getting stolen, dropping and breaking it etc. etc.
And for those of you who still think that it really sucks to be forced to do it - if CircuitMaker is a lot better than any of the other freebies around someone will crack the binaries and provide a server you can run locally to provide your own "Cloud" to the program...there's bound to be a few good software crackers in the hacker and maker community isn't there?
And personally, as a commercial user of AD and previous long-time Eagle user(and later a little DesignSpark) I think that CircuitMaker will be ages ahead in terms of usability and man-machine interface... I mean the community only suffers through what CadSoft calls an interface(I'd say it's more of the opposite - making the features as unaccessible as possible

) because everyone supports Eagle so nicely don't they? At least from the very few screenshots it seems they took a lot of the good stuff from AD over to CM..