I go to Columbia Law in NYC and want to pursue an LLM in corporate/commercial law. I've never been to London. I don't have as much of an interest in Europe as I do in Asia (but SOAS is out of the question for obvious reasons). Would you recommend UCL or Kings? What if I pursued finance instead?

Between UCL and Kings, UCL is far the better option for Corporate/Commercial. There is Prof. Michael Bridge in International Trade Law, Prof Graham Penn in International Finance, Profs. Calnan and Ron Harmer for Secured Transactions, Prof. Ian Fletcher - Corporate Insolvency, etc etc. Other heavy duty names in UCL laws include Prof. Phillippe sands QC of Matrix Chambers whose views are gold in several international dispute resolution bodies and Prof. Catherine Redgwell - one of the most eminent names today in Energy Law. If you re the type that revel in old names, fear not! UCL has a truckload of them: Ronald Dworkin QC, Michael Freeman, Hael Genn, Ross Harrison, William Twining, Sir Basil Markesinis QC, Prof Avrom Sherr and others too numerous to mention here.
Of course the intercollegiate system also permits you to "borrow" courses from Kings, SOAS or Queen Mary if you so wish. However, experience shows that its people from these Colleges who usually borrow courses from UCL, not the other way round!
Cheers mate. Hope this helps some.

In terms of reputation I would have thought that KCL and UCL were about the same. UCL has some great teachers at its law faculty (especially prof fletcher - his international insolvency course is very good) but then again so does KCL, particularly in the field of international finance-related subjects (eg Prof Dalhuisen, Toby Landau, Prof Matthews, Prof Hayton etc). Also, as bruce lee points out, given that the course is intercollegiate you only have to take two out of your four courses at the law school you're enrolled at. The others you can do at the other colleges if you wish.
As someone who did an LL.M in Corporate and Commercial Law at UCL I'd advise you to apply to KCL. The best course I took was a King's subject (International trust law - very interesting, taught to a high level by great teachers and excellent course materials) and I heard many good things about other KCL courses such as International Finance and International Arbitration. Also, in my experience UCL law faculty doesn't provide much support for its postgraduate students. Both senior faculty members and the graduate law office I thought were often arrogant and unhelpful. By contrast, my King's tutors helped me out a lot when I was applying for trainee positions at the commercial bar. So if were you I'd go for King's - but hey, that's just my opinion.
Best of luck with the apps.
MrK
PS I'm actually applying to Columbia and NYU this year to do an LL.M in international law. Any info you could give me on the relative strengths of these schools would be much appreciated.