Hi David,
Following the news reports here in South Africa, it seems as though the African Union is going on the offensive in a big way against the Somali extremists. What this might mean for your trip plans I don't know. it does seem like the focus is on the Ugandan government rather than attacking westerners.
Although it does seem like it is likely to be concentrated in Somalia rather than Uganda, but you never know how these terrorist groups will react to such actions.
Read further here:
www.mg.co.za/article/2010-07-28-africa-r...s-troops-for-somalia
I think the best thing to do is to get in touch with Jamie at Kayakthenile and ask, he would be the best person to give you an idea of the feel of the place at the moment.
Best of luck.
Scotty R