Thanks, Arne. I find the 16:9 format increasingly interesting, also for portraits, and my dream of an Xpan is slowly evaporating.
Godfrey,
You are right of course, although a Holga would be inconvenient for some kinds of work. What I do know, and this was part of the reason for my first post in this thread, is that most camera upgrades would mean marginal improvements to my photography, if any at all. Lenses on the other hand... lenses are religion.
re: 16:9 ... I like it a lot too, but I don't need the camera to enforce the framing. I have a standard 16:9 crop preset in Lightroom that I can apply (and often do as a default on import) when I have been shooting with the format in mind.
Regard camera upgrades vs lenses ... I've been quite happy with the image quality and dynamic range produced by all the 5Mpixel and up DSLRs I've owned ... I haven't really seen much difficulty even with the oldest of them (the E-1, 2003-2004 technology) and been able to produce superbly detailed and beautiful 16x20 and 20x24 inch sized prints from all of them. In general, I've found moving up to the 10-12 Mpixel range has provided a useful and well-worth it added amount of editing flexibility. More's better but comes at the expense of increasing space consumption and higher processing performance requirements.
Where camera body improvements continue to interest me is in the area of responsiveness. I don't mean "blazing fast AF" because I prefer to use Manual focus a lot of the time, I mean reduced shutter lag and fast shot to shot performance, quick writes to storage, etc. The E-5 is there ... I don't need any more than that camera provides ... but I'm more interested in the smaller cameras now. The Micro-FourThirds and NEX are ahead of the GXR in this regard (not sure about the X100), but none of them are quite up to the DSLRs yet. (It's a digression, but this was one of the reasons I moved back to DSLRs last Fall ...)
The Leica M is there already too. Since that's where I'm headed if I observe my current course. Since most of the lenses usable on the Leica M are superb, I'm kowtowing to the lens religion first while I assemble pennies towards the cost of the body.
Funny, but the Holga is there too on the shutter responsiveness ... ;-)