Walked to work tody, and was rewarded with birds that could have been swans. I only saw them fly overheard, and at first took them for geese, but there was something vaguely ungooselike about them. The bodies seemed slimmer, and the wings looked longer, and the way they moved seemed slightly different than geese, like the tips of their wings moved in a different way. The light was bad and I couldn't see any markings (which helps a lot) but what I saw of their necks looked white. When they called, it sort of sounded like an old-fashioned car horn going UHuh UHuh, a slightly more yodelling and trembling and delicate voice than Canada geese. There was just two of them flying together. When I looked up they were headed west but were in the process of making a slow circle to go east; a few blocks later I saw them (or another couple) again, this time deciding to go west after all.
They could have just been geese, too. I don't know swans well enough to be able to identify them by sillouhette and sound alone. All I know is that my girlfriend has been talking a lot about wanting to go out and look for the swans that could be flying overhead.
In addition to Mystery Birds, I also got to see the first crocus of the year coming up in somebody's yard, little white buds peeping up through the leaf litter on a warm, south-facing slope.