Those were not written by Ron... and he proposed his Monkey III before the other came out.
I'm hoping he'll use that old idea and story to make Monkey V!

Might & Magic 10, been waiting since 3DO went down.

come on, the might and magic series went down the drain after the 7th one

Been waiting for Fallout 3 since playing through part 2 around christmas 1998.

Now part 3 hopefully will be released in October/November.

I've been waiting for Jagged Alliance 2 to become abandonware ever since it was released;)

Loom was the best adventure game ever...too bad there were no sequels, even a spiritual sequel would quench me.

Propper Elder Scrolls sequel
X-Com (on earth and preferably with plausible game atmosphere)
Stalker: Clear Sky (soon)

It took Funcom ages to make a sequel to The Longest Journey, and now that they have Age of Conan to worry about it'll probably be another age until they make another... Especially annoying since Dreamfall ended on a giant cliffhanger.

Unlike many others I haven't really cared about DNF. There's been plenty of good shooters to fill the gap. What I have been missing is the space fighter genre, which died almost a decade ago.

Longest wait? Duke Nukem 3D :D

After what 3DO did with M&M IX, it might be wise to wait for Jon von Caneghem to get tired of his MMO venture. That could mean another few years.

Darklands is a candidate for longest sequel wait, certainly, though it's understandable. If you were a big name developer, you wouldn't want to put a lot of resources into a turn-based strategy title, or one that would require a lot of individuality in each of dozens of cities to give them character. An indie could do it without the fancy trimmings, and do it well, but the current license holder is being very tight-fisted about control of old Microprose properties. And that's not something an indie would willingly buck.