I've used two PS3s, with the same results in each case. Maybe I'm just lucky, but with such varying reports from different users, it's no wonder the problem was hard to pin down. But I do believe that it all goes back to the save file.
The massively different experiences people were getting added confusion to the collective fault finding the community attempted. You are only partly correct pointing at the save file as it's more the data that is tracked and stored there leading to the bloat. Things like dragons, other creatures, npc's not in your current cell but thay you interacted with hours before still being held and tracked even though you may be on the other side of the map. Pointless stuff being treated as near actors just adding to the system load and crippling the game. Bethesda said some months ago that the way we played and the order we did things in had the biggest effect on system performance.
I was the same way, but 1.7 hit me like a ton of bricks. Suddenly, I'm getting all of the problems other people reported - and I mean ALL of them.
Added as emphasis to what I said above, 1.07 will have done nothing to the savefile but it has the potential to cripple the game, even if it was working fine. It effectively kicked the scaffolding of the game and some of the platforms went wonky or fell off completely.
The chances of savegame corruption are what upsets me most as for many issues a deletion of gamedata and patch data followed by re-installation is needed with every attempt having the chances of corruption.
Before anyone gets picky as I stated patches don't modify savegames, they don't in a bug corrective sense but there is a capture process that marks the savegame as compatible with the patch version installed (Simple explanation).
