The Fairmont Vier Jahreszeiten is still my hotel of choice in Hamburg.

You'll find more detailed reviews in the Fairmont forum, but a brief summary of recent changes would be:

- the suites have been upgraded and could now be described as "modern luxury" vs. the previous "old-style elegance"
- the breakfast offering indeed seems to have gone downhill slightly, but is still good
- a rooftop bar / lounge area has been added (officially it's part of the spa afaik) which looked very nice
- service was excellent as usual