if the op is still reading and hasnt bought a camer yet heres my advice...
Sony:
still a newcomer to the DSLR market. i think they use the 4/3rds system? if not ignore that last bit. either way, they are still new, and hence they dont have many OEM(sony) lenses at the mo. the ones they have are nicely spec'd, and whilst i havent used a sony SLR yet, the lens prices, as with all things sony seem exorbitant, at least when compared to similar lenses from "camera companies" though, never forget that you can get some very very good 3rd party lenses now-adays! also of importance to note is that they use the konica-minolta lens mount, so they essentially have a back catalog of lenses available, though how old these lenses are, i dont know, nor how they compare AF and IQ wise.
i know nothing of their flash system sorry.
nikon:
obviusly a big player in the DSLR market, and now even more so with th D300 and D3.
they certainly have the pro-sumer(you!) section covered. their cameras are well spec'd and in that sense they match the canon's. note that pro-sumer nikons use a CCD sensor compared to canons CMOS. CMOS is generally regarded as giving better low light performance/noise, take this into acct if you plan on doing any indoor/pub/bar/club photography, or anywhere where flash isnt allowed. also note that the D40 goes to ISO 3200, whereas the 350+400D dont. other than that, the pro-sumer cameras your interested in are fairly similar.
nikon lenses:
they have a huge back catalog of lenses that can be used... but!!!!!!!!! and a huge BUT!!! the nikon D40+d40X dont have the usual inbuilt AF motor of the higher nikons!!! this means, correct me if im wrong here, that they can only use the lenses with an AF motor built into the lens itself!! and this will limit the choice to only the newer lenses or it MF for you...
(correct me if im wrong guys.) if you can use all types of lenses(aka, im wrong) then there is quite a selection to chose from, i think it goes way back to the 70'S? whereas canon only goes back to 92? though theyre pretty well covered...
nikon is generally regarded as having a wicked flash system, very easy to use and achieves great results easily. i havent had experience with it, but my 430EX on my 30D seems pretty damn good at bounce exposures...
canon:
my home brand. i love my 30D very much, but im very envious of the new D300
anyway, back to the point, pro-sumer cameras. we have 2 options you mentioned, the 350+400D both are great cameras, as mentioned above, very similarly spec'd to the nikons you mentioned. again, they use a CMOS, giving lower noise at high iso's. resolution wise, both the nikons and canon's and very similar, and unless your printing huge prints weekly, you wont notice the difference above 4MP, anythingg above 6-8 is more than enough for nearly every job, unless your cropping excessive amounts. also note, it is general knowledge that noise increases with higher density pisels, hence smaller sensor PnS's 1,2/8 sensor at 8mp produces horrible noise above 2-400 IS0. canon has a fairly well stacked lens line-up for the pro-sumer with many choices for budget wise people, there are soo many lenses that arent very popular focal lengths and so you can pick them up fairly cheap, thats if they suit you. the lens mount, compared to nikon is soo much easier, the XXD and XXXD lines take EFS and EF lenses, and thats all there is too it. canon is regarded as being the camera for sports and wildlife shooting, READ: long focal lenses, where-as nikon is thought more as a wedding and photojournalist brand. now this doesnt mean thats all they do, its just thats what people generally use that brand for. E.G nikon is said to have better tonal range and skin tones, ideal for natural skin for brides and for getting the black and whites from wedding pictures in the same shot.
canons flash system is pretty good, from my experience at least, my 430EX bounces well and gives consistent exposures all night long. and as usual there are many 3rd party options for lenses too.
small notes:
sony are the only company of the 3 to have in body IS, this means every lens essentially has image stabilisation, whereas nikon and canon prefer to keep it in lens. the advantages and dis-advantages of each choice is a hotly debated topic...
be aware of the nikon lens mount setup, i looked at going D200 a few months back and it was very confusing what features each lens could use and what lens i could mount, one thing i do enjoy about canon.
last note, a lot of nikons sensors are actually made by sony BTW, i think only the new D300+D3 are nikons own sensors, i think theyre trying to move it back home all round though...
and other than that, there isnt much advice i can give you, but basically if i had the choice again, id probably stay canon simply because of their lens sytem, its so easy to use and gives amazing results, now if i had the money to get a D2/300 i would have gone nikon as theyre isnt the compatibilty issues. you should research all this more, possibly on
www.dpreview.com ?
the only thing is when i started, the only cheap SLR was the 300D(im still a student) and so i went canon READ: didnt have a choice....
now-adays your very lucky in that nikon has some great competition for canon
and if i had more money, wouldve gone nikon
personally, id stay away from sony... i just dont like their system, and i generally dont like sony products in that theyre insanely overpriced for what they are when compared to other compaines! and that theyre lenses are VERY expensive and the choice is limited...
id also stay away from the 4/3rds system(Olympus and panasonic?, i dont see it being long term with the reduction in sensor manufacturing costs.... and youll be stuck with 4/3rds lenses that wont fit new equipment... not to mention its an even smaller sensor than APS so noise will be higher...)
so youve got a big decision ahead of you, chose wisely, and remeber, your not buying a camera, your buying a brand! its very expensive to change brands, i considered, and it'd cost me another $2000nzd to sell and buy equivalant of what i have now...
so consider all the factors and think about what you want to shoot, where you want to shoot, how long (timeframe) you want to shoot, essentially i mean if you dont want to do it as a hobby forever, with no plans to upgrade, then it wont matter what you chose really as things like nikons lens compatibility are pointless now as you dont plan on upgrading.....
wow that was really long, hope that it helps and didnt bore you, but its actually a very important decision
it was for me
catcha round-
-isaac-