So for the most part, each level needs ~31% more rating to get the same effect (alternatively, each time you level, your haste, etc., will drop to 76% of its former value).
At 90, you'll need about 3.9x as much rating as you have now for the same benefit. A minor benefit for people typing these numbers into spreadsheets, many of these are nice round numbers.
From Hinalover's Rawr link:
| 85 | 90 | Stat(s) |
| 265.08 | 1035 | Dodge |
| 102.45 | 400 | Hit* |
| 179.28 | 700 | Crit*, Mastery |
| 128.06 | 500 | Haste* |
| 102.45 | 400 | Expertise |
| 322.58 | 1259.52 | Druid agi->crit |
| 648.91 | 2533.66 | Druid int->crit |
| 884.04 | 986.63 | Druid spell scaling (what is this?) |
| 125 | 443 | Constant spell scaling (ability base damage?) |
| 11092 | 12567 | Boss armor (88=11977, 93=13452) |
* = Melee and Spell