Great news for SC2 map enthusiasts, Blizzard recently took considerations and increased the limit of map upload. Players may now upload 10 custom map and up to 50 MB of total map storage space.
From Blizzard Entertainment:
As part of our ongoing efforts to foster a productive and happy StarCraft II mapmaking community, we recently asked players to share their thoughts and ideas on how the custom map system might be improved. Some mapmakers noted that the current limits placed on custom map publishing felt too restrictive and, as a result, made their mapmaking experience less enjoyable.
We've taken this feedback to heart and increased custom map upload limits in two ways. Players are now provided with a total of 10 custom map slots and up to 50 MB of total map storage space. Ultimately, we want players to be able to share more maps with the community, and we feel these changes will supply mapmakers the additional freedom they need to better flex their creative muscles.
We'll be carefully monitoring how this additional storage is used by players and, as always, will continue to seek your feedback for how we may further improve the Battle.net mapmaking and publishing experience.