I agree; the updates sound like excuses and none of their claims hold together. Even if you believed 100% of what Namisu communicated to their backers, they are still handling the situation poorly; but it seems much more likely that they are simply being dishonest, trying to throw Bock under the bus to cover up for their own mistakes. Some details I found strange:
In their update at the end of October (the first delay), they specifically claimed that with their "professional fulfillment partner" there would be a two-week turnaround between receiving the nibs from Bock and shipping out the pens. In their latest update, they are scheduling a five-week turnaround despite working through the holiday season.
Next, they were set to receive the shipment of nibs mid-November. At the end of November, they are now claiming to be surprised at a further delay. Are we to understand that for the last two weeks they have been unaware that their nibs had not arrived? Or did it take two weeks to carefully write the update? There's no reason they should have left their customers in the dark if they knew far in advance that there would be further delays and complications.
They also claimed that shipments from Bock had previously taken 6-8 weeks, and that this time has taken double that. In reality, by the time their new projected date rolls around, it will have been 20 weeks. Unless they were late in ordering the nibs to begin with, those numbers don't add up.
Finally (this one is more guesswork), previous Namisu pens (Nova and Orion) use stock #6 Bock nibs with no custom engraving/scrollwork/etc, and unless they are using a different nib size for the Ixion, there is ample evidence that they have an inventory of Bock nibs. Their other models of pens are in stock on their website, and they are currently running two deals on Massdrop, available with both Steel and Titanium nib options (these are the same Titanium nibs that they singled out as a cause of extra delay). I think it's reasonable that a bulk order of extra nibs for the KS project would stress the supply chain, but you would expect a company that consistently uses the same supplier to have at least a reliable channel of communication to sort these things out.
I know that Kickstarter campaigns have an inherent risk as far as fulfillment goes (I just received a KS item last month that had been promised in 2013), but as Namisu is a fairly experienced company by now, I expected better. It seems they are simply taking advantage of the Kickstarter platform to mistreat their backers without repercussion; I doubt a customer using their actual website would receive such poor customer service.
Sorry for the very negative post, but every time I tried to objectively read their updates, more inconsistencies and contradictions jumped out at me. In fairness, I should mention that I've purchased Namisu pens before (not the KS versions, but their production models from their online store) and have been happy with the quality, and I do believe that they will eventually deliver another quality product. I just dislike the way the KS campaign is being handled.