Hmmm, I read the article and paid great attention to the benchmarks. 4890 tends to score better.
Here, read the FPS results for yourself all run by Extreme Tech at 1900x1200 (from about 22" to 27" monitors).
far cry 2
COD5 World in Conflict
Company of Heroes
Stalker Clear Sky
OCUK Price of 275 229.99 GBP inc VAT
4890 209.99 GBP inc VAT
So to say the 275 takes the cake is rather a strange view.
Nvidia and AMD are both very savvy and big organisations. They have products aimed at all market sectors now. From budget gamers to bleeding edge competition sponsored gamers.
TBO, to choose a graphics card today, you have to know which games you play. Cos both Nvidia and AMD have roughly equivilant cards for the performance and the budget. Yup, it's that close a race!
The other factors you have to consider are
Chosen output? (pretty much determined by your optimal flat panel resolution these days!). No point looking at 24" panel resolution results (1900x1200) when all you have is a 19" (1280x1024)
How pretty you like it? Note the two values above. The second value is lower as it uses AA at varying levels. Think of it like putting the roof down on a convertible car. Car looks and feels great, but the performance hit is quite noticable.
Similarly to cars, some ppl can't live without that AA feature turned on (along with AF too!). So when comparing the numbers, find out if those features are essential to you.
NB: DO NOT USE THE ONBOARD GRAPHICS RAM AMOUNT AS AN INDICATOR! The graphics card manufacturers these days have cottoned onto that one. It's a bit like having 16 valves on a ford fiesta 1.1L. it'll improve it but in the end it's still a tiny 1.1 litre engine. Similarly with graphics cards.
Now I'm not espousing Tomshardware, but this page is the only one with a complete hierarchy that i've found that shows a rough relative performance with older cards too, so you can really see whether it's worth an upgrade.
Also has some mobile graphics cards listed too, so you can see what portability is costing you performance and price wise!