In reply to Fredt:
I was pondering this the other day as well.
From:
http://www.cosleyhouston.com/kenya-eq-list.htm
Footware considerations for Batian
Climbing Shoes - On Batian, what to wear on the feet for the summit climb is not a straightforward question.
Option 1 - We prefer to start from camp wearing a very light rock/mountaineering boot which we will wear up through the initial pitches of climbing to the Amphitheater. Good, lightweight examples of this sort of boot are the Sportiva Trango "S", or the Salomon Pro Rock - both quite rigid, with low profile soles. If you adopt this strategy, be sure that you can climb 5.7 rock in these boots.
Above the Amphitheater, we switch to loose-fitting rock shoes, leaving our boots at the Amphitheater. Rock shoes make the climbing go faster and more enjoyably. Be sure your rocks shoes are comfortable for many hours on end of climbing. On the way down, we switch back to our boots at the Amphitheater.
If the route high on the mountain is snowy, we may choose to bring our mountaineering boots to the top as they perform well in these "mixed" conditions.
Option 2 - You can also wear rock shoes right from the start of the technical climbing. In this scenario, you can hike up to the start of the climbing in your walking shoes, switch to rock shoes at the first pitch and remain in them for the entire climb, up and down. This makes the climbing a bit faster, but can be cold on the feet in the predawn pitches, and tiring or painful after a long day. Also, the scrambly, somewhat loose nature of the first few pitches is not as well suited to rock shoes. But they'll work and be fun to climb in.
One disadvantage of this option is that potentially snowy conditions in the upper mountain can make for slippery and cold feet, if all you have are rock shoes. To deal with this you may need to carry your walking shoes to the summit. This works, but such shoes may not perform well on the occasional rock moves high on the peak.
Option 3 - There are many "hybrid" rock/approach shoes out there as well, and these can be a good choice so long as you can climb well in them at difficulties of 5.8 and 5.9. These shoes have the added advantage of light weight, a bit of warmth and good scrambling ability.