Here you go, Euan:

Click on the image from a large version. The white vertical line is 10 km. The area of the enclosed area is 400 km^2. The green diamonds are rigs and the green dots are "new" wells.

As far as rigs go, here are excerpts from the Saudi Aramco 2006 Annual Report:

We have embarked upon an expanded exploration
program, designed to grow our proven reserves of oil
and natural gas both onshore and offshore. With our
greater emphasis on increasing production of natural
gas to fuel the domestic economy, our major discoveries
in 2006 were gas fields. We plan to drill more than 300
gas development wells and 230 exploration and
delineation wells by 2011. In the next 10 years, we hope
to add 50 trillion cubic feet (tcf) to our current 248.5 tcf
of gas reserves.
...
One of the central components of our expansion is our
drilling program. At a time when worldwide demand
for drilling rigs is at historic highs, we increased our
drilling rig count by 26 percent, from 90 to 113 rigs.
This total rig count comprised six exploration rigs and
75 development rigs (65 onshore and 10 offshore). In
addition, we deployed 32 workover rigs (24 onshore
and eight offshore). We drilled 368 new development
and 13 exploration wells, and performed 206 re-entries
and 136 workovers.
More than 80 percent of all wells drilled in 2006 were
horizontal wells with either single or multiple laterals.
...
Crude oil increment drilling continued throughout the
year, including the completion of 73 wells for the Haradh-
III increment, 28 of which were MRCs. Drilling for the
AFK increment continued with 54 wells. We began drilling
for three other crude oil increments in 2006: Khurais,
Shaybah and Nuayyim. The Hawiyah gas increment drilling
program was initiated, with 32 wells planned.

I suppose one could derive the rig residence time from this data.