no, i don't think it will ever die, but like most product lines it will ebb and flow with the economy, buying tendancies etc. For a variety of reasons (labour problems in chinese factories, slow down of chinese factories for olympics, huge spike in oil, 21c losing the WM deal etc) there has been a big lull in 1/18. But new items will come, probably at a slow pace and then one day that pace will no doubt increase again.
There is also the FOV wildcard to consider. From all reports, the Bravo Team line did very well, which is very promising for future, and no doubt better quality releases.
There will occassionly be other toy lines to the rescue as well, such as the IJ line, with its long desired items such as a german truck, sidecar motorcycle and russian troops.
But if you want to be constantly busy adding new things to your 1/18 collection, then you're either going to have to branch out your interests (i collect not only military, but sci fi, cars ,motorcycles, animals/dinosaurs, ships when i can, historical figures and on and on, all in 1/18 ) OR take matters into your own hands and start customizing, going a bit off scale (many combine 1/16 with 1/18, for myself i have several planes that are a bit off 1/18 scale but huge and cool nonetheless), use other products like r/c aircraft etc.
Many board members already do some or all of the above things to keep themselves busy. Others jump ship to another scale, which is fine. But for those who are addicted to the big scale then you have to get creative and a bit compromising....or go to a smaller scale, buy yourself a magnifying glass and good pair of glasses and be prepared to be let down alot by the small size of the items.
I have considered 1/32 many times but, while the variety is undeniably much better it still ain't great and i never felt that giving up the huge wow appeal of 1/18 was worth it for the small gain in variety. And if you combine 1/32 with 1/35 for greater variety well that's pretty much the same as going off scale with 1/18 (to 1/16 or 1/20), so why bother to leave the scale you love? The only true scale that has spectacular variety is 1/72 but they are just so small i can't get even a little bit excited about them......they don't convey and of the majesty any presence of the real thing.
i never met an airplane i didn't like...