This article from the BBC reveals that South Korea may delay food aid to the North since Pyongyang failed to meet the deadline for shutting down the Yongbyon reactor.
The two Koreas are slated to begin economic discussions on Wednesday, at which point the issue of rice aid was to be discussed. Previously, South Korean officials had stated that the aid would proceed regardless of whether or not the Yongbyon reactor had been shut down and sealed by the deadline. Pyongyang had asked the South for 400,000 tonnes of rice aid.
Now however, it appears that Seoul has taken a new stance as the 6PT deadline has come and gone. South Korean officials met Sunday to discuss the next steps. One official told a Korean paper, "We can't just ignore and do nothing if... North Korea doesn't take initial steps [to meet February's agreement]." (That reminds of the "Super Kim" video below. I found it with subtitles and it turns out his "Special Move" is to "ignore and continue.") I find this stance somewhat encouraging and a little bit surprising. It's nice to see the usually accommodating South Korea put a little more muscle into the disarmament/peace process.
The article also mentions the Japanese reaction - very hard-line - and references the "China wants us to wait" line that Larry first brought up. In retrospect, it is entirely possible that there is more to this than just U.S. domestic posturing. China might have something up its sleeve to sway Pyongyang (or China's banks). Maybe the 6PT is more of a multilateral effort than I gave it credit for in my previous post.