Many articles on the web tell you that the choice of camera body doesn’t matter because photographers change their bodies much more often than lenses. In this article I’d like to offer a different point of view.
First, a body without lenses is not very useful so when we first choose a body we always pick one or a few lenses to start with and this way the choice of lenses is a consequence of the choice of the body we make. Next lenses in line tend to complement the ones we bought with the body.
Second, digital SLRs are now a mature technology (unlike 4-5 years ago) and choice of a body becomes much more important since there’s not anymore a good reason to switch to the latest camera model every 2 years as we had been used to doing.
Third, with the important switch of Canon, Nikon, Sony to full frame for high-end cameras, this choice becomes much more important because upgrading crop cameras (smaller sensor) to full-frame practically means that you’ll need to replace all or a majority of lenses even if you decide to stick with the same manufacturer and mount. Here I have to admit Nikon wasn’t honest to their customers when saying the future was with the DX (crop) format and that there was no need to go to full-frame. As it turned out (and could be predicted by their consistent lack of primes for the DX format) with Nikon D700 they changed their policy and now support full-frame for a wider range of users. Although technically the differences in quality are not so important, the biggest difference is that the DX format doesn’t offer lenses for photographers like myself who like to shoot with primes only. Actually, the offer of zooms is also much better for full-frame, especially with all the zooms for film cameras on the second-hand market.
Another argument which can be made is that new photographers need a few years before finding the style which will suit them best. We mostly start with cheap zooms, the wider the focal range the better, then we discover we may like extreme wide-angle or telephoto shots, or we like bright lenses for the narrow depth of field or possibility to take night shots. Or, perhaps, we don’t like carrying around heavy and huge universal zooms around and would much rather switch to discrete small, light (and cheap!) primes. Such discoveries usually mean we are forced to buy new lenses or replace existing ones.