In a similar vein, and I think possibly the answer is in the comments section from the point of view of what are Toyota doing next, this was on the Autocar website:
http://www.autocar.co.uk/blogs/new-cars/opinion-what-new-land-rover-defender-must-beat
The problem for both LR and Toyota is that basic, robust vehicles don't make money - it's a lot easier to make a big fancy thing with lots of gadgets and gizmo's that people will pay a healthy premium for. In part this is why FIAT haemorrhage money - the cost to make a Panda isn't dissimilar to making a Mercedes S-Class, but nobody wants to pay S-class prices for a Panda, and as all FIAT really make are small cars, they are always in a bit of a problem. Extending that, if you want to make money I remember reading the break even point for a mass manufacturer was over 500,000 cars per year; this is why SAAB went kaput (as well as being screwed over by GM) Now that this is well known, and certain markets are targeted due to their massive growth (think China and India) opportunities, manufacturers are shifting their product ranges to match - some companies are presenting a premium range for those markets (Volvo for example) whilst others are re-hashing discontinued products that have amortised all their development costs (VW and PSA)
But how is that relevant to the fate of the Land Cruiser? Well, to amortise the development costs of a new vehicle the volumes have to be kept pretty low, and if that isn't managed then there has to be scope to sell a lot to make it cheaper. Realistically the development costs and costs of production lines can be recouped in about 4 years of production, and after that it becomes a much more profitable line (depending on costs and volumes) - this then begs the question as to why 70 series and G-wagens are so expensive!
Lastly, don't forget how much things have grown - my 4Runner is not that old (24 years old) but a current generation Xtrail (I know... a Nissan...) is about the same size as it, and is beginning to dwarf an 80 series...
4Runner: 4.49m long, 1.68m wide, 1.679 tall
X-Trail: 4.64m long, 1.82m wide, 1.709m tall
80 Series (no flares): 4.82m long, 1.83m wide, 1.785 tall
200 series: 4.95m, 1.97m, 1.88m
Based on the assumption that every new version is going to be bigger and better, how big would a 300 series end up?!
For me the ideal size vehicle is about 4.75m long, 1.8m wide and 1.75m tall (I can still load the roof easily then) but with decent clearance and a 3.5 litre diesel engine (like the B-series or P-series Toyota engines)... also know as a BJ73 or PZJ73 Land Cruiser!