What? NOBODY mentions the major reason why identity fields were frowned on? Has this reason disappeared? Each insert is going to the same page, at least until the page is filled and even in 2005 that will cause a page lock until the insert finishes. (No more inserts allowed until the transaction commits.) It caused the term "Hot Spot" to be invented. Also the problem with the old datetime format when trying to insert by date when you have 20 records waiting to insert in the same 3 millisecond gap. (When your key was just a datetime field)

Since when does sequential mean organizing data together? We've had two uniqueindex, clustered, primary key fields in one table. The first identifies the client (the value found in another table) The second is definitely unique in the table because it is always generated with a newid() value when inserted. This definitely organizes the data together because everything is retrieved for the client when a client shows activity. Now that's organizing data together using a completely random identification process.

I feel for the person with the deadlocking problem. That's an argument among a host of reasons why artificial keys like identity fields are better than natural keys. (Keys, whose values have intrinsic meanings.)