Hey everyone, great to see the excitement and abition still going. Even with Skyrim out now, Morroblivion is still a blast.
Porting Oblivion into Skyrim isnt strictly impossible, but it may as well be. There are some things we'll need first (and it could be monumentally difficult). The different game engines makes something like this MUCH harder than coming up with the original Morrowblivion converter.
However, ALL HOPE ISNT LOST. If a conversion program is to be made, there's one way I can see it happening, but it'll take time, and programmers (my friends and I are can program, but we're... novices when compared to a task like this). A rough way to think about it would be in the following easier-said-than-done-steps.
1)We'll need to know the internal file structure's for oblivions esp's (that is, we need to know how to read from and write to esp files). Fortunatley, this has been done already, there are a number of programs made by modders that can open up esp's, tinker with them, and re-save without a problem. Unfortunatley, there dosnt seem to be much information that I can find on how to actually do it, but we know its possible.
2) We'll need to be able to do the same thing with Skyrim's mod-files. The construction set is comming, and its only a matter of time before the file structure is figgured out. We're lucky that bethesda gives us so much access to thier files and modding tools, if this were a different engine, decoding the filestructure would be even more of a pain in the ass. But this is something we'll have to wait for, unless some tallented programmers come our way, and we'll still have to wait for the construction set to even begin.
3) Write a program that reads data from an oblivion esp, and inserts it into a Skyrim one. This part will take a tone of work, there's an endless amount of things that can go wrong, and it's a huge task (and its madness). It should be possible, because for MOST things in Oblivion, there will be an equivalent in Skyrim. (e.g, NPC, worldspace, dialog, item, activator). But we're going to need to know the file structures inside out! We'll need to interpret every piece of data about every element in the oblivion esp, and understand where we need to put it in the Skyrim one. How that data needs to be rearanged, what data needs to be left behind because Skyrim dosnt have a place for it, and what data needs to be fabricated with a placeholder because Skyrim has something new that wasnt in oblivion.
Its possible guys, but i think we'd almost be better off doing it manually, and either way could take years. Although seeing as we have a lot more activity on the site now days, it could be possible. To do it manually, we'd start with the world space, maybe try to take the heightmap from oblivion and generate it in skyrim. Then... the rest is just incredibly daunting.
I think everybody should just enjoy our achievenents in Morrowblivion and the new and shiny Skyrim for now. Once the construction set is out for a while, maybe there'll be some developemts that'll make this task possible, for now though, anything we start is going to run into a solid wall very fast, and the project will probably stagnate for a few years anyway like Morrowblivion did all those years ago.
I'd love to see it happen though. And I'm sure we arent the only mod community thinking about doing this, someone else might surprise us with a way to begin in the future!

Maybe the other way,put
Maybe the other way,put skyrim into the oblivion engine,there is already a place for skyrim on the oblivion map and it is just a short walk across the border,no sea.
But either way the file structures would have to be understood,and headers converted.
And then all content from skyrim would have be converted to oblivion counterparts,otherwise we would be doing time for real without a lockpick,:)