Personally, I think that exclusives should always remain exclusives. Like when I first bought my Playstation 1, I bought it so I could play Tony Hawk Pro Skater. My N64 didn't have it, and I doubted it would be coming there.. almost a year later it comes out for N64, almost improved in every way for the exception of videos. I felt like I wasted a good sum of my own well earn cash because a developer didn't keep their word.
Granted, my Playstation became my most used console shortly after when i found myself indulged in games like Syphon Filter, Metal Gear Solid, and Gran Turismo.. but for a short while, I was pretty pissed with Activision and Neversoft for lying to me.
So when I see games like Bioshock, possibly MGS4, and some other titles, I just get upset that developers (or publishers like Konami) go back on their on screen notices like "This game is EXCLUSIVELY for the PS3". These are just my thoughts though, on the other side, I don't believe any games should be exclusives except for the Company Mascots like Mario, Master Cheif (I suppose), and Crash Bandicoot (when he was the face of Sony Entertaintment).
In short, no, LBP shouldn't be ported anywhere. They advertised it as an exclusive, they should stay true to their word.
EDIT: Into further over-thinking, I find myself wondering... Who is SCE 'mascot' character now? Sackboy? Rachet & Clank? Nathan Hale? Solid Snake?
