I am curious, how is loading handled in game likes WOW? Anyone know?
In Guild Wars, when you go to any other area than the one you're in now (leaving/entering a town, entering the next area of a mountain range, traveling to another continent) you get a loading screen. When you've recently (as in, during the last hour) been in that area it takes only a few seconds, if you've been there longer ago, or worse: never, it can take a few minutes.
Mind you, these times are on my computer, wich only just makes the minimum system requirements.
I think seemless loading is great, but may not be always practical. High-end computers can probably manage seamless loading, but what if you're playing on a computer wich barely meets the requirements? I think they would start lagging whenever the player even comes near a new area. For this reason I suggest that maybe you could have a setting wich allows you to choose wich to use, something like:
[ ] Use seamless loading (the area you are approaching will load in the background)
[ ] Use a loading screen (any new area you enter won't begin loading untill you actually enter, and you will see a loading screen till it's fully loaded (greatly increases performance on slow computers))