Nikon is a business. When you have limited resources, you prioritize based on profits and opportunity.
I don't have visibility to Nikon's volumes, but I'd guess the D300s has never been a high-volume camera for them. I'd go as far as to say it is the lowest volume platform other than the D3x. Also, I work in the technology industry, so I understand fairly well how far in advance these kinds of products are planned and how delicate some of these supply chains can be for custom, fairly low-volume products.
But whatever, what I'm trying to say is I think your frustration is a little pointless. I'm not saying that to be mean or challenging, just honest. I'd really, really like to have a D400 as well, but my career background gives me the opportunity to look at it from a business perspective - I can understand their decisions. I can wait. My current camera still works fine.
As for the D800 debacle, I think Nikon is getting a bad rap. There is only so much production capacity they can afford to build - it doesn't make sense to build extra for a short-term bubble. Building up stock before the announce has significant financial implications (many countries tax inventory, etc.). Lots of people have three or four on order in different places and will cancel the others when they get one, or worse go on Buy/Sell boards and try to make a quick buck. The 5DMkIII isn't the big leap from the MkII that the D800 is from the D700. No surprise there isn't a massive swing to the stores, thus less demand, thus better supply. (I'm not implying that the 5DMkIII isn't a good or successful product BTW).
For everyone complaining about the D800 inventory, I'm yet to hear a suggestion that is viable from a business, legal and financial perspective (I haven't even heard many real suggestions beyond "they should make more."). I wish it was legal for them to require a non-refundable cash deposit for the early orders. That would clear out the multi-orderers and the quick-buck guys. Unfortunately it would make too many people mad and I doubt they can legally require it of their resellers.