In Raising the Banner, GU #49, there will be a significant change to experience.

The amount of experience needed to progress from levels 20 - 70 has been lowered to allow a speedier progression for people playing in those tiers. This is especially good news for all you altaholics out there!
Now it will be faster and easier to rejoin your friends with the new you! With this change, it is possible that people who are close to their next level may ding, but no one should ding more than one level.

As an added bonus to the increased experience gain, the drop rate of Adept I spells and combat arts, will see a healthy boost as well. This will enable people to more easily upgrade as they progress through the levels. This is a great time to take up transmuting too!

If you need any help convincing your friends to mentor and help you along, there are also some major changes to the achievment experience gained through mentoring. While players are mentoring a lower level friend or guildmate, they will now receive more achievment experience than they did before.
Additionally, the larger the gap in levels, the more exp you can get! If you are mentoring a friend 51 or more levels below you, you will earn a 300% bonus to your achievement experience gained through combat or loot items. You will also receive the bonus whether your apprentice has their combat exp enabled or not.

With all these changes coming, we've got one more surprise in store! This weekend, September 26-29, there will be the first EVER double experience weekend! It'll be a good time to break out those dusty alts and stretch their legs!