Tite Kubo's BLEACH had it's beginnings in the japanese magazine "Weelky Shonen Jump", in August 2001 and grew more and more popular since then. Thanks to very skilled Scanlators the series became available for the "wide market" of the mangafans who were moving in the scene online. Since that time either Manga and Anime were licensed in the USA.

Similiar to Naruto it appears that the Anime had been slightly overhauled for the US market. "Appears" because there were not hard facts to be found online until today, we're still waiting for an official statement of the TV station.
An apparently constant change was that the picture was brightened while a Hollow is near (due to the not perfect quality of the records the quality of the screenshots made from the US version isn't perfect, though I did my best to overwork them for the best possible quality - my apologies though). Though nobody would notice the minor changes, unless you compare both versions.

Besides that the credits in the opening and ending were translated into english of course. In the US version the B-Opening was used from the start. This is identically with the normal opening, yet some animations have a better quality than the original opening (for example the hairs of a girl are streaming in the wind, while they aren't in the original version). The song is still the same too. The credits in the ending are running much faster than in the original version.

An example for the opening and ending:

The order for comparisons is:
Left: Japanese version
Right: US Adult Swim Version

This report is about:
Episode 01
US title: The Day I Became a Shinigami
Japanese title: Shinigami ni natchatta hi (死神になっちゃった日)

About this episode: The changes in this episode are very minor and you can only say about one edit that it's kind of censorship, if you want to. This is the last edit as the blood of a Hollow was reduced. But since you could see a lot of blood before, also running directly out of wounds, I think it's just supposed to be little "beauty correction". The blood removal during the death of the first Hollow is definitely a correction, since it's just not logical that blood is flowing out of the sides when the slash was made vertically.

In this episode was, not counting opening and ending, no time difference.

0:07:51
As the Hollow destroys the building and you see him in the middle of a smoke cloud, the smoke has been overhauled. The contours are much sharper in the US version, while the look almost blurred in the original version.

No time difference

0:07:59
The position of the Hollow has been changed.

No time difference

0:08:31
As Rukia kills the Hollow, you can see something red flowing out of the Hollow's sides, most likely it's supposed to be blood. This was removed in the US version.

No time difference

0:21:32
As Ichigo kills the Hollow the animation was slightly changed. In the US version there is far less blood, but the trace of Ichigo's slash can be seen longer.

No time difference