As was revealed at the season-ticket holder sessions in November, the Cubs are going to celebrate each decade of Wrigley Field's history in successive homestands, and will also be wearing throwback jerseys (hopefully, the opponent that day will do the same) honoring different eras in Cubs history.
Via the great site SportsLogos.net, you can have a look at all of the different jerseys, including the one you see at the top of this post, which isn't a throwback per se -- it's supposed to be an "alternate road jersey", paying homage to a style of road jersey worn between 1920 and 1925, and also worn at home during 1921. (Many thanks to Chris Creamer of SportsLogos.net and to Matthew Robins -- @BupsJones on Twitter -- for the photo above.)
While I understand the idea behind this jersey, I don't care for its execution. The piping adds an unnecessary detail that gets in the way of the logo -- and the numbering style, which is clearly meant to be similar to the block lettering style, is different from the number style the Cubs have worn almost consistently since the 1930s. (There were no numbers on Cubs jerseys until 1932.)
The other jerseys -- nice work, as you can see at the link. Each one is meant to echo a specific era in Cubs history and does so quite well. I especially like the zippers on the 1940s era jerseys -- authentic to what was worn in that era.
But the road alternate -- I understand the motivation behind it, but the execution leaves something to be desired.