I'm under the impression that due to the PS3's wonky method of scaling, 720p native titles played on a 1080i/p will always look better when played back on the 360. This was painfully obvious with VF5, but that was quite a bit ago.

Has anything changed in regards to what developers have been doing with the scaling tech?

It has gotten much better. The launch titles that were 720 only wouldn't upscale to 1080. Now, devs are using custom resolutions to up them 1080. Not sure if it is customer damand, more experience, or the updated SDK, but 480/1080 TV owners like myself sure appreciate it...

Just look at Uncharted for instance, looks great when scaled to 1080i!

there are still games being released that lack upscaling. Mainly from ea, I think Turok also. the PS3 has not changed its scaling ability and it is still up to the developers to include scaling, Sony has not mandated 1080 support

Just look at Uncharted for instance, looks great when scaled to 1080i!

Depends on where you live:
http://www.eurogamer.net/article.php?article_id=90995

Yeah, if developers add it, games at higher than their native res look great. I have both my 360 and my PS3 set to 1080i for my 768p set. But since some PS3 games don't support it, I still have to change my display settings back for those games. A little annoying, but not that big a deal.

DVDs, though, are scaled beautifully on the PS3 universally.