HERE is an interesting article/statistics I found.
Rolex seems to be the only watch brand that gets into top 100, in the overall brand ranking. Cartier, Hermes, Bvlgari and Tiffany are there as well. I think they all make watches too. No TAG or Omega.
I don't know how can you actually measure "brand value"... and this definitely isn't "brand prestige" ranking.
For people who don't want to go through the whole article, here's the top 100:
Rank, Brand $million
1 Coca-Cola 67,000
2 Microsoft 56,926
3 IBM 56,201
4 GE 48,907
5 Intel 32,319
6 Nokia 30,131
7 Toyota 27,941
8 Disney 27,848
9 McDonald’s 27,501
10 Mercedes 21,795
11 Citi 21,458
12 Marlboro 21,350
13 Hewlett-Packard 20,458
14 American Express 19,641
15 BMW 19,617
16 Gillette 19,579
17 Louis Vuitton 17,606
18 Cisco 17,532
19 Honda 17,049
20 Samsung 16,169
21 Merrill Lynch 13,001
22 Pepsi 12,690
23 Nescaf