This is both News and Rumor!
As of this date Canon has not made an official announcement that they are recalling the Canon 24-105 IS L lens. However, Canon USA reps have been quoted as saying to consumers "Canon will make an official recall announcement next week." In the meantime some consumers were instructed to send the lens to Canon and were mailed/emailed a free label.
This lens has a "flaw" - a specific type of flare that appears on the image when the light is at a certain angle. See my image below shot with the Canon Rebel XT and 24-105 IS L. This is an "L" lens that is priced at $1250 and above.
In the meantime, the 24-105 has been one of the most sought after Canon lenses since it started appearing in Japan, and finally the USA a few weeks ago. Shipments left the stores the day they were received, and it has been almost impossible to find a copy. For almost 2 weeks, there have been no shipments from Canon. It is "rumored" that Canon has stopped all shipments and even production of this lens.
On a personal note, I would not have paid much attention to a little "flare" until it showed up in some of my images (see below). With this image, the "rays" of the flare just happened to land in an appropriate place as you can see. However, it is not something I would want on too many of my photos, nor would I want to "cover" the top part of the lens every time the sun came out which is what some people are doing. Not for $1,250!
This post will be updated with any Canon official announcement/press release.
Liz