LR3 & LR4 Noise reduction

Are there any improvements in noise reduction between LR3 & 4. I'm using a mac and last night was doing environmental portraits of a woman with my Canon MKIII with ISO's up to 2,000 and the results were exceptional. I processed generally in LR3 without noise reduction, did some touch up in Portrait Professional and when I came back to LR3 I only had to use a little noise reduction and this amazed me with the results.

So what I'm wondering is, can I push this higher ISO even further with other options for noise reduction i.e. LR4 or any other software. I've done lots of shooting at the higher ISO's with this camera but generally never felt that good about it over 1600 ISO. If I can go further, it'll open me up to some more lighting experimenting which I'm doing out on the streets just before the ambient light moves to dark.

I have been happy with the noise reduction in LR4.1 but didn't use LR3 enough for a comparison. I know my 7D (and even my old 20D) allow me to get into much higher ISO than I would have thought reasonable. I've found ISO 1600 to be easily doable if properly exposed and I shot some stuff at ISO 6400 yesterday - church worship service - and was satisfied with the outcome.

I would expect your 1D MKIII would be a great deal better with high ISO noise.

The NR is the same in 3 and 4, but what is new is that NR is on the Local Adjustments Brush now, which means you can do extra NR in areas where it is needed more, such as shadows or out-of-focus backgrounds where it is less concealed by detail.

Well that's pretty neat.

Well a friend told me that the switch from LR3-4 is like getting a new camera, both of us have used LR since they first introduced it and we both shoot MKIII's so I'll take that as making it worthwhile to try, but I have only 4G of RAM in my iMac so I'm going to download the trial version first. I just tried to log onto Adobe but got a message that their server is down or not connecting.

Ram is cheap - bump it up....

A few more details on the brush NR: It is Luminance only (the reasoning being that chromatic noise is uniform throughout the image, so a global Chromatic NR suffices, and besides, the default 25 setting is right for 99% of images.) Similar to brush sharpening, the brush NR uses the concurrent settings in the Detail panel but varies the strength - thus, if in Detail you have set Amount 20/Detail 60/Contrast 40, the Detail and Contrast will be 60 and 40, but the Amount will be 0 to 100% of 20. So the most NR you can apply in a single brush is a doubling of the global NR, but for smaller amounts very fine adjustment is possible.