This is simply a case of adding consumer options, which is always preferable, both to the consumer as well as to the vendors.
Any way you can get your content to the end user is the key issue.
Is everyone going to start switching to DL on PSN now that it's available? No way. But the additional option for renting and buying constantly refreshed content is there.
The lack of ability to purchase HD downloads (which are limited to 1280x720) means that it's aimed squarely at the rental market, which is considerable.
Do highly compressed 1280x720 files match Blu-Ray quality? Don't kid yourself.
For the non-renters (primarily videophiles), they're still going to opt for higher res, lower compression 1920x1080 Blu-Rays every time.
Even when wide area increased bandwidth network standards are increased, DL files will still always be compressed higher resulting in lower image and sound quality. I don't see 25-50GB DLs on the horizon any time soon.
Sony doesn't directly benefit by the rental of B-RDs, as much as they would by "renting" video files direct to consumers who already own a PS3. They do still benefit by sales of discs to rental services, which is not insignificant.







