Because keeping all of those quotes, notes, and rumors in one post is getting lengthy, let's break this down by team in separate posts. As these come in, they will be updated and reposted.
Latest status: Interested, but a longshot
Washington Post (5/23):
While General Manager Mike Rizzo did not confirm or deny the interest, he intimated the Nationals have been active in pursuing players and praised Oswalt.
"We have interest in a lot of people," Rizzo said. "We're always on the phones, we're always doing our due diligence on players. Oswalt is a tremendous competitor and a tremendous pitcher...Whether or not the Nationals want to acquire Oswalt, it seems unlikely a deal could be struck."
The Nationals are looking to improve their rotation and have expressed interest in trading for Astros right-hander Roy Oswalt, according to a baseball source. The Nats have not confirmed that they have interest in the Astros' ace, and Oswalt's agent, Bob Garber, did not return a phone message Sunday.
If the Astros and Nationals can work out a deal, Oswalt, 32, and right-hander Stephen Strasburg would be a perfect 1-2 combination in the rotation.
Buster Olney (5/22):
"The feeling among rival executives is the Nationals are apt to be very aggressive before the trade deadline, the kind of team willing to take on a contract -- like Oswalt's -- that might appear outsized to other teams. Washington's window of opportunity is opening, and the promotion of Storen so early tells us that they will work like crazy this summer to climb through."
Buster Olney (5/22):
The Nationals are thought by other teams to be in position to be aggressive, if the front office decides to make moves. But Oswalt would have to approve a deal to a franchise that hasn't been in the postseason in almost three decades, and to a team that lost 103 games a year ago.
Sporting News (5/22):
He'd be the perfect mentor for Stephen Strasburg and bring immediate legitimacy to a rotation that still is a weakness. Washington, though an up-and-coming franchise, isn't a bona fide contender yet and plays in a loaded division. Thus, Oswalt could exercise his no-trade clause to block the deal.