Rough draft:

In Batmud, most of the unique rooms that any player can reach give experience for visiting them the first time. The idea is to get players to explore the game’s areas and reward them for doing so. Ideally, you’ll take the time to actually find out how difficult the areas you visit are, and search for secrets if the area is not too dangerous. Death is an inevitable part of exploration, but you can still get a huge boost to your experience by engaging in this activity.

Generic rooms that exist simply to fill out a mapped region do not usually give explore. They’re just carbon copies of each other.
Level restricted, aka ‘newbie only’ rooms do not give explore. These include rooms in: The newbie mines, hakkrio forest, past the iron plates in the Arelium dungeons, the fraggle village, the paladin stronghold, the conifer forest, and a small part of the chessboard.

Guild rooms which can’t be reached unless you’re in that specific guild do not give explore.

In fact, if it would be impossible for some players to reach a room without reincarnating, it usually doesn’t give exploration experience.

                                Exploring
                               -----------

The realm of Batmud is huge, and there is a great variety of
areas and sites to see and explore. The number of rooms of the mud which
you have explored, along with the total number, is displayed with the
'score' command.

You will gain experience points when you visit new rooms. The actual amount
of experience will go up exponentially when the number of the rooms you have
visited grows. Exploring is a good method of character advancement, 
especially at the lower levels.

There are special rooms that give a substantially larger amount of experience
when you explore them (for the first and only time). You will be informed
when you enter such a room. To prevent abusing a constraint has been placed
that limits the maximum experience gained from these special rooms to 
the experience gained from visiting normal rooms. The possible additional 
experience, however, is not lost. The system keeps count of it and awards 
you extra the next time you visit a special room, assuming that your normal
explore has gone up enough to allow for this.

Special rooms are rather rare, and there are areas that do not contain a 
single one of them. 

These exact figures are not available for the eyes of the mortals, neither
are the formulas. See the table at the end of this document for getting an 
idea about the experience you can expect to make from exploring.

Note that certain areas (such as guild rooms or level-restricted
areas, or the outerworld map) do not count in the total number of rooms, and
thus you do not gain experience for entering them.

See also: 'score'.

 The following table will give you an idea of rooms/experience ratio...

 ,--------------------------------------------.
 | Rooms visited          | Experience gained |
 |--------------------------------------------|
 |   100                  |      5000         |
 |   500                  |     85000         |
 |  1000                  |    300000         |
 |  2000                  |   1000000         |
 |  4000                  |   4000000         |
 |  6000                  |   8000000         |
 |  8000                  |  15000000         |
 | 10000                  |  23000000         |
 '--------------------------------------------'