I have yet to see any of the gurus of silicon hubs clearly define how an area can promote these qualities or even how one might identify regions with the desired qualities. The last two commonly-cited ingredients, the presence of large technology companies and the availability of venture capital funds, are effectively the same thing. It's the same to lesser extents with giants like Cisco, AOL, and Compaq, who invest in promising technologies with an eye toward future acquisition. Investment does not always come from the biggest kid on the block. But the reason an area draws the attention of investors generally comes from the presence of the local success stories.
Money is an eminently portable commodity.
Venture capitalists go where they see past success, unless someone convinces them to take a long shot, and they can do that anywhere in the world. Further, both of the above factors are not so much factors as results. Close examination shows that the circumstances in the development of nearly every one of these areas have been unique. Have someone born in your city who is extremely smart and ambitious, has the good fortune to turn those qualities into the founding of a leading high-tech company, and loves the area enough to want to keep his or her company and home there. If that sounds like the real key is luck, we might finally be getting closer to reality.