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Which harmonics standards should I be concerned about ? 

Anyone who is selling electrical products that connect to the AC line in to Europe must test to IEC61000-3-2.  
61000-3-2 describes limits and how those limits are applied to harmonic measurements.
Annex B of 61000-3-2 states: "The requirements for measurement equipment are defined in IEC 61000-4-7"
61000-4-7 describes exactly how the harmonic measurements must be made in terms of measurement techniques, equipment and measurement uncertainty.

What’s new about 61000-4-7?

Now EN61000-4-7 2002 is very different to the previous version in that it describes in great detail the requirement to measure inter-harmonics at 5Hz intervals. (50,55,60,65... instead of 50, 100,150 Hz...) The inter-harmonics are then grouped into the normal 50,100, 150....Hz intervals such that the limits of 61000-3-2 can be applied as usual.

This has a big impact on the measurement hardware because 10 times the processing is required in the same real-time duration (200ms).
There is confusion because a small clause in the 2002 version states: "The use of existing measuring instruments based upon the requirements given in IEC 61000-4-7 (1991) continues to be permitted until the next revision of this standard".
It can be argued that this clause still applies, but:
CENELEC list EN61000-4-7 2002 as current with a DoW (of previous version) of 2005-10-01.
CENELEC list EN61000-4-7:1993 as "Replaced / Withdrawn"
EN61000-4-7:1993 is no longer available from the BSI website for example. (Listed as withdrawn).

So to be up to date check your measurements are to EN61000-4-7 2002 and include inter-harmonic groups.

Caution:

Because the inter-harmonics are grouped before checking against the limits of 61000-3-2 there is very little difference in the format of the displays and reports that you will see when making measurements.
The actual measurements can be significantly different however. Products where current is drawn asynchronously of the ac line show significant measurement differences. A laser printer is a good example of this because it carries out all its principle functions, like moving paper, with no connection to the input line frequency and drawing significant current at inter-harmonic frequencies.
Good manufacturers will supply evidence of the inter-harmonic grouping in action in the form of third-party calibration data.

What's new?

Quite a lot! For the latest information and your free copy of the renowned 'Voltech Handbook of Testing Harmonics and Flicker' please contact us and we will be happy to provice you with a copy of this excellent technical resource.