Is best of breed dying?

There was a time when vendors and enterprise customers touted the technical and business benefits of best-of-breed (i.e., picking the best of the best and integrating them into a coherent solution tailored to a company's needs). Recently I started hearing vendors talk about the value of single-source vendor solution (whether it is hardware or software).

Is this a reaction to a rise in the number of failed (or expensive) integration exercises? Or is it as a result of vendor consolidation - with some of the bigger vendors now capable of offering one-stop-shop. For example, EMC can now offer security (RSA), server virtualization (VMware), Data Deduplication (Quantum, Avamar and now Data Domain).

I raised this question within the Storage Group community of Linkedin and got a couple of interesting responses one of which has specifically asked not to be made public in case he gets into hot water because of his opinion.

My own observation is that it depends in part on the customer. I spoke to the head of IT at Bossini and he said that best of breed works for them. 

In the instances where I've seen best of breed fail, it is rooted around compatibility and accountability issues that no one anticipated at the beginning of the acquisition trail. Consider the case at a large Philippine-based conglomerate. The company upgraded their storage hardrware, deployed a SAN, and installed a new backup software. Pre-production testing was good. A few weeks after going into production one of the database applications started to issue error messages. Initial investigation by the data admin pointed to the new storage system as the culprit. This was validated by the database vendor. Two weeks of research on the part of the storage vendor revealed the problem was not inherent in the storage system. The storage vendor showed postings on several user groups showing the same problems but with different storage platforms. So whose fault was it? Worst of all, the problem took three weeks to solve.

The point of the story is that throughout the first two weeks of problem solving, no one wanted to take accountability. When the bulication is not working and the organization is losing money because it is unable to take in orders, who is at fault? Who should be responsible?

What is your view of this?