To me über, used in this way, denotes a feeling of exaggeration but can also imply one of envy and distate (both fairly English characteristics!)which is only slightly disguised by the use of a foreign word (albeit used out of context). As with most languages, we seem to feel the need to borrow words from other languages (and other contexts) to make us feel like we are taking our own language to another level. All it really does, most of the time, is make us seem pompous (another fairly English trait!).

I love it. It has the merit of being instantly understandable, and it neatly contains the idea of "surplus" - with philosophical under- (or, rather, over-) tones of transcending 'normal' morality. Also has connotations of 'exuberant', which has an udder origin :)
Etymology: Middle English, from Middle French, from Latin exuberant-, exuberans, present participle of exuberare to be abundant, from ex- + uber fruitful, from uber = udder.
Vache à lait ?

I like it too, especially as I can't think of an English word which carries as much depth of meaning. In French, an excellent equivalent would be "richissime", as pascalc tells us on the French side. But in English?

We just call them 'the super-rich', don't we? (We = those of us who live in the UK). There are an awful lot of them these days. I wish they would go away and London prices could go back to normal. :-(

PS. Hang on, does that mean that there is now another level of 'super-rich'? :-(

I was told the other day that a salary of £25,000 (not what I'm getting, far from it, unfortunately) was 'peanuts', 'really pathetic'. Time to emigrate, maybe?

Good question: are the über-rich richer than the super-rich? And I wish they stopped buying weekend pads in Brighton, for the same reason!

Uber has an edge of contempt and envy (such a tediously typical British combination) that super does not. I have seen Uber-yogi (i.e. someone who is able to do amazingly physically difficult yoga, like the astanga 3rd series)

If you are keen to enrich your French language vocab., here are some words/phrases describing those who are über-well off. (!!!) with varying connotations and degrees of wealth

richard (derogatory) (as in : C'est un richard) / il est plein aux as/ il en a plein les poches/ il est riche comme Crésus / il roule sur l'or (cousu d'or) / il est hyper friqué (NOT über-friqué ;-) / il est bourré de fric/ c'est un nabab / un nanti / un rupin / un milord

I hadn't thought of "über" connoting any idea of contempt or envy, simply the idea of excess or surplus - probably because most of my translation work is from German into English.

But what's most interesting about borrowings from other languages is how they become embedded in the other language and how the meaning can actually change. Those who get bees in their bonnets about überborrowings would do well to consider this.

I'd propose "super rich" or even "obscenely rich" to describe some cases.