The MLSD is now updated through games of June 22nd.
In addition, I've now run through the entire season of the Venezuelan Summer League, which started play on May 15th. I haven't fully integrated the VZL into all the menu pages, but you can click here for a complete list of VZL players. There are a few weird things about that--some of the links don't work because of the incomplete integration, and three VZL teams have multiple affiliations--but the data is all there, as usual.
Also, I've started compiling data for all the other rookie and short-season leagues: the New York-Penn League, the Northwest League, the Appalachian League, the Pioneer League (which includes the Helena Brewers), the Arizona Summer League (which obviously includes the AZL Brewers), and the Gulf Coast League. However, those leagues are less than a week into the season, so I haven't bothered to generate pages just yet. I expect to have all leagues available on or before July 4th.