From the wires, and I quote:

"Altman Weil is pleased to announce a strategic alliance with London-based Jomati Limited. Like Altman Weil, Jomati is an independently owned global management consultancy advising law firms and corporate law departments. It is led by Tony Williams, formerly the worldwide managing partner of UK-based international law firm Clifford Chance and worldwide managing partner of Andersen Legal.

"Both Altman Weil and Jomati focus on high-level work involving strategy, merger, financial performance and organizational structure, and share a goal of providing clients with sophisticated, innovative solutions to management issues. By allying, Altman Weil and Jomati broaden their capabilities to serve legal organizations throughout the world. Both organizations were involved in the two transatlantic mergers of US and UK law firms announced in 2004. Altman Weil advised DLA in the recent DLA Piper Rudnick mega-merger. Jomati acted for Kirkpatrick & Lockhart in their combination with Nicholson Graham & Jones.

"Because an increasing number of US and UK firms are considering the possibility of a transatlantic merger, there is a growing need for advisors with breadth and depth on both sides of the Atlantic. This alliance will allow us to provide in-depth, on-the-ground, consulting services to clients in the UK, Europe and Asia, multiplying the value either firm could deliver independently to law firms with an international agenda."

So what?  Actually, so a couple of things:

• The study of market structure tells you that the geographical footprint of service-providers (Altman-Weil, Jomati) to an industry (the AmLaw 100 and UK 100) should align.  Simply put, you want to be where your clients are.  Seen this way, a better question than "why?" is "why not before?"
• Globalization is proceeding apace; it is increasingly limiting to have critical mass only in London or only in New York.  And the divide between the US-based and the UK-based firms is starting to look flimsy.

Combined with last month's news about Thomson acquiring Hildebrandt, the legal-consulting industry also appears to be consolidating in mimicry of its target clientele.  The interesting question now becomes whether these deals will have any impact on the relative success and failure quotients of US firms targeting London and UK firms targeting New York.  Up until now, it's fair to say the former efforts have fared far better than the latter.

Why is this so?  I'll resist the glib temptation to attribute it to some nebulous and self-congratulatory "entrepreneurial" blood in American veins which is hypothetically lacking in English veins; that "explains" precisely nothing. 

Rather, I have a more straightforward theory (Occam's Razor, anyone?):  The UK partner lockstep-compensation system operates potently to inhibit them from paying gunslinging New York rainmakers—who they need to build a presence here—what they're worth on the open market.  The daytime drama that has been Clifford-Chance's embrace of Rogers & Wells is only the most conspicuous example.  (I have faith they're sorting it out, but the point still obtains.)