You would probably get better replies at dpreview.com

Thanks and I'll try there...

As per TA forum:

I came across this:

northlight-images.co.uk/Canon_new_lenses.html

and this

northlight-images.co.uk/cameras/lenses/ef_20…

I'm wondering if, if and when it does come out, it won't be especially pricey given the effects of the earthquake.

As a side topic, I believe you've been to Selous. I'm thinking of going there, Selous Impala and Lake Manze Camps. Do you have experience with Lake Manze Camp? Thanks, Steve

sdb2, I had a fabulous time in the Selous, but only at Impala and fly-camping (before going to Kwihala in Ruaha). Wanting to go back at a different time in the season, Flo at Adventure Camps has booked me both Lake Manze and Impala for October '11.
When are you thinking of going?
To wet your appetite, have a look at http://www.adventurecamps.co.tz/selousimpalagamediarypre2011.htm and scroll down to my reports, Dominic.

PS have decided to rent lenses for my June Serengeti trip, going with the Canon EF 24-105mm f/4 L IS USM and the EF 100-400mm f4.5-5.6L IS USM

Hi, Dominic. Thanks for the link; I enjoyed looking at your report and other photos.

I had plans to leave in 2 weeks, but an illness in the family might have me rescheduling for September/October. I was going to do 5 nights SIC and 3 nights Manze. I've read people at some forums suggest 8-9 days in Selous is overkill. Do you agree? I really enjoy wild dogs and would like to have as much time as possible to photograph them (like you I once saw a wild dog kill and was amazed at how quickly and how organized the eating was). I also like bird photography and Selous seems like such a good place to do that. Do you usually arrange for your own car? I think you were there in June. Was it busy there?

You're carrying 2 excellent lenses. I usually carry the 28-135 IS (though I don't use this very much), 70-200 L (F4) and 100-400 L lenses. The 70-200 is my favorite---what amazing color and sharpness, plus it's easy to handle as compared to the 100-400 (though it's the workhorse on safari) ---and I usually will have it on a second body. Last year heading out of Wilson to the Mara it looked like I was going to have to take either my photo gear or clothes, though that wouldn't have been a big decision for me. In the end SafariLink just charged a nominal overage fee.

I appreciate any thoughts you can offer. Best, Steve

Steve, it's a tough one to answer. June was brilliant in that there were very few people at Impala, so I effectively ended up with a guide and driver to myself. It is greener, with the animals more spread out, but they are also less stressed than during the dry season. Patience is the key in Selous, with high rewards (as per my Sunday). The birding was spectacular, especialy by boat along the river & lakes. I do still need top-tips for shooting birds in flight tho'.
One thing that Selous offers that does make an extended stay more attractive is it's range of activities. Boating, fly-camping, bush walking (excelent for all the little stuff missed by driving) and even some fishing are all on the agenda, so you can interspace these into your game drives.
The xtra time spent would allow time in the two main camps and a good middle period fly camping.
Again, a good chat with Flo at Adventure camps should tailor make your needs with the best number of days.