Yes, Eurogamer clearly has an agenda they push. For example with regard to GTA IV they compared the cinematics which on the PS3 was claimed to be 24 FPS (like holywood movies) and on the 360 30 FPS. Who is even going to notice this?
The differences between 360 lead games and their PS3 ports are very minimal (which is not surprising considering the technical differences, despite the PS3 is more powerful). Even with the worst early ports which used very little of the PS3's resources they weren't as if you were playing the Wii or PS2 version. 
99% of the games are nearly equal with both versions showing stronger and weaker points, it's not like developers have twice the amount of enemies on screen compared to the other version or anything major like that. Mostly it's just a different color scheme, with one version looking a little clearer but with more aliasing issues and the other a little more blurry, one a bit darker or vice versa. Minor stuff like that many would only really notice when put next to each other. but using a different HDTV screen or minor changes in TV settings will often have a bigger impact.
But most agree the most impressive and best looking games are on the PS3 already, Uncharted: Drake's Fortune, Metal Gear Solid 4 and Killzone 2 are some real eyecatchers and the gap will IMO get bigger as time goes on.