Source: http://maplestory.nexon.net/WZ.ASPX?PART=/News/View&boardNo=200&contentNo=005Ug&pageIndex=1

EXPlosion Changes Now Permanent!

The Maplers have spoken, and we hear you loud and clear. You loved our EXPlosion event so much we’ve decided to make the changes to our EXP curve a permanent part of MapleStory. Now not only you, but all future Maplers will enjoy an easier leveling experience!

Dear Maplers,

We have confirmed that Monster Books are still being shuffled for some users. This issue will be completely resolved during next week’s game update.

We apologize for the inconvenience and thank you for your patience. 

This server maintenance has been postponed to Thursday, July 23rd, 2009.
A separate notice will be posted with more information.

MapleStory will be going through a scheduled maintenance on Wednesday, July 22nd, 2009.
 
This maintenance will involve all game servers, and it will last approximately 4.5 hours.

 <MapleStory Server Maintenance>

 – Server : All Game Servers

 – Time : Wednesday, July 22, 12:00 AM – 4:30 AM PDT

       (Wednesday, July 22, 7:00 AM – 11:30 AM GMT)