Nepal has been mentioned here a few times, and as I have trekked there about 8 times since 1984 I though I'll share some experiences and thoughts.
My first trips were in -84 and -85 as the beginning and end of a 7 month Asian journey Nepal-Thailand-Burma-Thailand-Hong Kong-China-Tibet-China-Nepal. I carried Olympus OM-3 and OM-4 bodies with 21, 50, and 135mm lenses + Widelux F7 panoramic camera. They were all squashed into a small camera bag, and at worst I had 270 rolls of KodaChrome 64 in my backpack. That trip, by the way, produced quite a lot of good and even great photographs, and sales to magazines, travel agencies and even stock via Magnum paid for the whole trip both for me and my wife, even though it was not a work trip at all. Places like Nepal, Burma and especially Tibet were so seldom visited at that time that those pictures had good novelty and sales value.
In October -84 we hiked about 26 days the old long Annapurna Circuit including Annapurna Sanctuary, Dhumre to Pokahara, no roads at that time at all. In April-May -85 we hiked Jiri-EBC-Jiri 42 days, including visit to camp 1 on Everest West Ridge (only two expeditions…), crossing Amphu Labtsa and summiting Mera, all without any permits, of course. Those were the golden days of trekking in some sense, still rustic and basic and no crowds and no roads.
Later I have returned to hike AC about three times more, EBC/Gokyo also three times more, also Manaslu Circuit attempt and Naar-Pho valley and Tilicho Lake crossing to Jomsom. I have also dragged about a dozen friends to trek with me, some of them have also visited Nepal over 10 times since.
What comes to footwear 80% of the time I have used either trainers (in eighties) or trail runners (Solomon XA Pro 3D Ultra GTX are my favorite). Much lighter and nimbler than boots. We always use porters and if there are more then just us in the group, a guide also. One 32 day trek was done as camping trek, 7 "members" with 31 crew, still costing only 47€/day all inclusive. This was the Manaslu Circuit/Naar-Pho/Tilicho trip where there were no lodges available (in 2009). As a cool-off we hiked ABC again and made a quick visit to EBC also, 12 days Kathmandu-EBC-Shivalaya walk-out, pre-acclimatized as we were.
Trekking in Nepal is much simpler than people think. It is easy to arrange a private trek even with porter etc, still having full control of the timetable and route. It is not necessary to "book" a prearranged trek where you are shepherded along with others on fixed schedule. It is also much cheaper, costing now typically around $40/day in a small group with guide and couple of porters. That includes food, bed and salaries, cheaper than living at home…
On my later treks I have carried either small point&shoots when shooting video mostly with a fairly big video camera (Canon XH-A1) or Canon 5D with 24-105mm or Nikon D800 with 24-120mm. On my later treks I have not used a camera bag, camera is either at the top of (or on the top) my daypack just under the lid, fairly fast access, or hanging by my side/neck. If raining and I want to keep the camera out, I wrap it into a SeaToSummit silnylon bag, which we use for all clothing & sleeping bag also to keep them dry. Porters carry our things in waterproof or resistant duffel bags, which they prefer to backpacks.
I usually get one small stomach upset once a month on average, more a nuisance than anything bad. Twice I have had giardiasis, which is easy to treat with Tiniba. I have never used or needed Diamox, as I, and we both, acclimate extremely easily. We avoid eating uncooked vegetables and only drink treated water. In eighties there was no meat available along the trails, now we do eat an odd yak steak if the meat looks and smells ok. Trekking is my favorite way of weight control, I loose on average 1 kg per week by eating frugally and by constant exercise.
I am eagerly waiting my retirement in 3 years, already making plans to go back and explore some white areas on my map, like Tsum Valley, Langtang-Helambu and unexplored side valleys of Khumbu. Just hoping to have also the right side hip joint replaced by then… Long range dream is to combine Naar-Pho, upper Mustang and Dolpo into one great excursion lasting about two months. Those areas are still quite untouched by tourism.
If you are interested in seeing some pictures check my Picasa albums, there are two albums from Nepal, Annapurna Circuit in 2004 and 52 days of trekking in 2009. No artistic intent, but at least a 10% filter was applied when choosing the pictures instead off just dumping the memory card to the web.https://picasaweb.google.com/109958612223411682295