I think more major releases should be accompanied by browser-based mini-game teasers. It's a relatively cheap way of getting some viral exposure, and - well - it generates a fair bit of good will. Here are two examples available this week.
The Madworld website offers three mini-challenges, based on Platinum's hyper violent sci-fi shocker. In Bullseye you throw objects at your human targets, using deft mouse control to aim. Head Ball has you controlling two characters indulging in keepy-uppy - with a decapitated head. Finally, there's Human Hammer, a version of the track and field event, hammer throwing, but with a person - thrown toward a series of deadly obstacles. The visual style is minimalistic with stickmen and monochrome visuals, but it's very funny, and the commentary at the beginning gives a good hint at the style of the full game.
While you're at it check out the Patapon 2 mini-game, hosted by SPIL Games (also available at the official site here) and developed by 'digital engagement' specialist, Kerb. It's a diddy rhythm action treat in which you follow the correct drumbeat sequences to command your soldiers. The sound effects are great and the visual style matches the PSP title.
Enjoy!