there is no such thing as immediate "automatic" scaling (at least not in the sense as amazon makes it appear). That said, Yes Scalr is pretty cool, in fact it

there is no such thing as immediate "automatic" scaling (at least not in the sense as amazon makes it appear). That said, Yes Scalr is pretty cool, in fact it is almost a godsend for high traffic apps out there... but take this with a grain of salt- establishing server farms using pre-built generic AMIs to load balance your databases can come at a cost...literally. Scalr still has some way to go but it sure does look promising.