I haven't used the online playstation store much but you can browse content on their website.  I think the difference between PSN and XBLA's content is that you will be able to download the content to your xbox even when you're not at home.  The catch is that it will have to be in sleep mode similar to when you turn background downloads on and turn off your machine.

There is an option for downloading games for the PSP on the PSN website though.

If it did, you would see the horde of ps3 fanboys come and post how x360 is stealing ps3s features. If it didn't, than you'llsee all the ps3 fanboys come and post how this is worthless feature and how it will fail.

As for now, i'm leaning toward the second scenario.

The PSN does. PS Store on PC.

No it doesn't (for the ps3 at least), and the question was never about whether PS store was available on the PC. I'm looking on wikipedia and the ps store website now and I see nothing that says people can use the PS Store and have media downloaded to their ps3 while they are away.

Unless of course you're talking about the PSP, in which case why even bring it up and try to compare cars to bicycles.

Not a bad idea at all, but one thing that i wonder is, that will this mean that gaming forums get marketers (bots?) that posts links to the XBLA titles?