Not sure how up to date this is though.
The developer doesn't get any money directly. They get whatever they agreed with the publisher. Although many times the publisher owns the developer so it's all going to the same place anyway.
The amount saved from selling digital copies really depends on how much the digital store front charges for sales. If they take the same % than physical retailers do then the saving would be minimal. Of course for those that are the publisher and the store front (eg. Sony, Nintendo, Valve etc.) then it's quite a big difference regardless.