This year I continue to try "old glass" on my Sony Nex-5, while anxiously awaiting the NEX-7 with its built-in OLED viewfinder.
Here is a handheld shot with a 30 year old Nikon zoom at 200mm. The small image is a 100% crop of the top of the building. Look at it in "original size" in Flickr...click on the photo, then click on "view all sizes" and click on "original"....you can even see shingles on the roof of the tiny cabin, but in the full frame, you can barely see the cabin ! No sharpening was done.
I still find the lenses from the 1960's to 1990's sexy ... I used to lust after these babies when I was a teenager with my first Nikon, but they were so expensive. Today they can be purchased (used) for a song, as everything today is autofocus and auto-everything.
I have always been a Nikon fan, and especially because their newest cameras (D3, D700, D7000) can still mount Nikon lenses made since the 1960's. Pro's know that their main investment is in the glass, and the cameras bodies come second. In the end, camera bodies are just boxes that let in light. Today's pro lenses are still metal, but the consumer market lenses are mostly plastic crap that rattles if you shake it.
Today i'm testing a lens that I have had for more than 30 years...a Nikon 80-200 f/4.5. This baby was over $750 when it was new in 1975 (I paid $450 for it used in 1982!), but today you can find them in garage sales and on Ebay for $50 or less. In REAL camera shops,they still cost around $250 in good condition. This lens was manufactured from 1969-1981...typical for Nikon lenses back then. Today's plastic zoom wonders rarely last 5 years before they are replaced by a new design/model. Just try getting one cleaned...apparently the lens assemblies are glued into the tubes...no screws or rings, so they can't be disassembled. If it gets fungus or needs cleaning, touch luck. Just buy another one.
Somehow, pro photographers used lenses like this up until the 1990's when autofocus became popular. They had to set the shutter speed based on moving subjects, or set the aperture based on what type of DOF or bokeh they wanted. And they had to focus manually .... ! Geez, how did they manage without 359-point autofocus, face detection and 8D Matrix metering?
I find it fun to use these lenses, because it makes me slow down and think about what I want to show, whereas with auto cameras I would just squeeze off 10 shots of the same thing (and then have to edit tons of identical images later).