Send in the clowns

CBS has announced the participants of The Amazing Race All-Stars (beginning 19 February 2007, Manila time) and I have three questions for the network...
1. Where are the clowns (Al and Jon, Season 6)?
2. Where are Colin and Christy "I hate you!" / "My ox is broken!" (Season 5)?
3. Why Romber (Rob and Amber) again?!? I guess so that I'd have a team to loathe.

Anyway, check out the teams:
1. Joe and Bill "Team Guido" (Season 1; third place) — partners
2. Kevin and Drew (Season 1; fourth place) — buddies
3. Ozwald and Danny (Season 2; fourth place) — friends
4. Teri and Ian (Season 3; second place) — married
5. John Vito and Jill (Season 3; fifth place) — now ex-lovers
6. Charla and Mirna (Season 5; sixth place) — cousins
7. Uchenna and Joyce (Season 7; winners) — husband and wife
8. Rob and Amber (Season 7; second place) - professional reality show contestants/
newlyweds
9. Eric and Danielle (Season 9; separate teams) — met as Amazing Race opponents
10. Dustin and Kandice (Season 10; fourth place) — beauty queens
11. David and Mary (Season 10; sixth place) — cuddly marrieds i.e. Kentucky!!!