DATE 2.0 - consolidated

 The links below only represent a fragment of the (>600 million) dating market. Although I think that 1:1 dating isn't even really Web 2.0 (the matchmaking concepts in the list below come closest to that), the sector is interesting because it's quite mature, a lot of money is going 'round, and some of that is spent on innovations that sometimes spill over to 'real' 2.0 categories.
Of course a lot more flirting & dating is going on in the category COMMUNITIES 2.0.

Airtroductions - 8 miles high dating
Collaboradate - Meta dating website (Stealth)
Conservativematch - Only for rednecks
Doubledate - Pair up with friends
Eharmony - Dating for not so young people
Engage - Matchmake for your friends
Flirtomatic - Flirt & date
Gottaflirt - Flirt game
Greatboyfriends - Post & match your brother's or sister's profile
Honestyfirst - Dating for honest people
Hotornot - Geo dating (map mash-up)
Impersonals - Date without being creepy
Itsjustlunch - Lunch dating for professionals
Kisstokiss - Dating
Matchactivity - Connect to likeminded people
Meetmoi - Mobile dating
Paird - Social matchmaking
Plentyoffish - Reallyreallyreally free dating service
Rateordate* - Crowd match, singles event maps, online dating
Singlesearch - Two way matchmaking
Social21 - Be matched & date
Subwaycrush - Dating(?)
Tantricsoulmateconnection - Matching based on horoscopes etc.
Togetherdating - Dating after personal introduction
True - Dating, free of married people and other criminals
Verbdate - Speak up before you date
Wecheese - Proximity based dating
Weeeh - Free dating (Stealth)
Youmeus - Relationship advice community

Update 061221