Canon Rumors has posted this:

CANON INSTANT REBATES: May 3 - July 11, 2009

Camera Bodies

EOS 50D Kit + EF-S 18–200mm f/3.5–5.6 IS - $300
EOS 50D EF-S 18–200mm IS Kit - $300
EOS 50D EF 28–135mm IS Kit + EF-S 18–200mm f/3.5–5.6 IS - $300
EOS 50D Kit + EF 70–300mm f/4–5.6 IS USM - $150
EOS 50D EF 28–135mm IS Kit + EF 70–300mm f/4–5.6 IS USM - $150
EOS Rebel XSi EF-S 18–55mm IS Kit (B) + EF-S 55–250mm f/4–5.6 IS - $200
EOS Rebel XSi EF-S 18–55mm IS Kit (S) + EF-S 55–250mm f/4–5.6 IS - $200
EOS Rebel XS EF-S 18–55mm IS Kit (B) + EF 75–300mm f/4.5–5.6 III - $100
EOS Rebel XS EF-S 18–55mm IS Kit (S) + EF 75–300mm f/4.5–5.6 III - $100

Lenses

EF 200mm f/2L IS USM - $500
EF 85mm f/1.2L II USM - $130
EF 70–200mm f/2.8L IS USM - $200
EF 100–400mm f/4.5–5.6L IS USM - $100
EF 16–35mm f/2.8L II USM - $100
EF 50mm f/1.2L USM - $100
EF 24–70mm f/2.8L USM - $80
EF 70–200mm f/4L IS USM - $75
EF-S 17–55mm f/2.8 IS USM - $70
EF-S 10–22mm f/3.5–4.5 USM - $50
EF 17–40mm f/4L USM - $50
EF 70–200mm f/4L USM - $40
EF-S 17–85mm f/4–5.6 IS USM - $50
EF 100mm f/2.8 MACRO USM - $35
EF-S 60mm f/2.8 MACRO USM - $30
EF 28–200mm f/3.5–5.6 USM - $30
EF 28–105mm f/3.5–4.5 II USM - $20
EF-S 18–55mm f/3.5–5.6 IS - $15

Flash Units

SPEEDLITE 580EX II - $50
SPEEDLITE 430EX II - $30
SPEEDLITE 220EX - $30
MACRO TWIN LITE MT-24EX - $70
MACRO RING LITE MR-14EX - $50