Gigapixel heightfields:
For a stress-test of L3DT's tile caching system I generated a 32k×32k pixel heightfield. Without erosion, it took nearly 5 hours (AMD XP2600). With erosion, it was a bit over 17 hours. No problems were encountered.
Progress report:
I've updated the to-do list again. The last few items for L3DT 2.3 are proving difficult, but not insurmountably so. The release date is uncertain, but some time in June seems as good a guess as any.