That’s my first thought, too. How do we know what was tasted is attributable to the can itself?
Yep.
I really dont want to do this but my curiosity is peaked now…
Going to check the dates on the bottles/cans and I’ll go with Coors
Another point of differentiation…conditioning vs force carbing. A lot of microbrews still bottle condition I gather so one would need, when extending the tests to microbrewed samples, to ensure that the bottled samples were force carbed as well. The difference there (between natural and force carbonation) I think would be substantial, with a refermentation and a conditioning period. Also, I wonder about flash pasteurization, that could also account for differences. Do they flash pasteurize before or after packaging?
When we’re done with this we can test my ability to taste “steeliness” when beers are fermented in stainless steel fermentors. :D Here’s an example of one such beer reeking with steel flavor:
The 8% steel reserve wasn’t bad, especially if someone presented it to you as a maibock.
Interesting…
Maybe it was because the cans didn’t turn blue to show you it was cold enough…or it wasn’t beechwood aged ;). Cans are lined with plastic so there shouldn’t be any contact with the metal. Denny if you are looking for a craft beer that comes in both cans and bottles, I know Brooklyn Lager does…I’m not sure if you can get that readily in Oregon.
Fat Tire also comes in bottles and cans
So does Moose Drool.
This will set some of you back then too… my brother inlaw only drinks Miller HL (about 40 years now) and he won’t drink it from a bottle because he prefers it from a can… and he can taste the difference. You should have seen his face when I had him try an IPA. 
;D I laughed so hard I almost fell out of the chair. ;D
What if the cans are actually keeping it fresher, and the taste you are getting is the true taste of Miller Lite?
Okay, let’s assume there is a difference, since you guys can taste it…where does the difference come from? How does it relate to the packaging? Those are the real questions now.
Was your test MHL?
If so, then the difference could be a different recipe because it comes in a clear bottle as opposed to the cans.
I was searching for finished beer pH on google and came across this study below. We don’t have a good reference for what the stated levels of aluminum in the beer mean, but it at least indicates that aluminum does leech into packaged beer over time, and does so faster at room temperature vs. refrigerated temperature.
[quote]Detection of aluminum residue in fresh and stored canned beer
This article is not included in your organization’s subscription. However, you may be able to access this article under your organization’s agreement with Elsevier.
M. M. Velaa, R. B. Tomaa, , W. Reiboldta and A. Pierrib
a California State University, Long Beach, 1250 Bellflower Blvd, Long Beach, CA 90840, USA
b Weck Laboratories, Inc., City of Industry, California, CA 91745, USA
Received 23 May 1997; accepted 29 September 1997. ; Available online 30 October 1998.
Abstract
The United States produces about 200 million barrels of beer each year from which a large percentage is packaged into aluminum cans. It is important to identify the possible effects a particular foodstuff may induce on its package especially when it is being purchased and consumed nationwide on a regular basis. Very few studies have been done on aluminum can corrosion by beer. The purpose of this study was to compare aluminum levels in fresh, and stored, canned beer representative of U.S. quality draft. A 2 × 2 × 4 design was employed for two brands of beer, A and B, held at two different temperatures of 23 °C (room temperature) and 5 °C (refrigerated) over a period of 5 months. Room temperature beer was found to contain more aluminum (108μgl−1) than refrigerated beer and brand A at room temperature had significantly more aluminum content (546μgl−1) than brand B (414μgl−1) at the end of the duration of storage period. Aluminum content changes from day 0 to day 150 were significant. From these results, it is shown that aluminum cans are corroded over time by canned beer. However this corrosion may be reduced through refrigeration.
[/quote]
Interesting. One thing I wonder, since that study’s from 1997, is if/how the lining of cans differs between then and now.
I’m willing to bet that for the big players like BMC, the cans aren’t very old when they fly off the shelf. Probably packaged only a day or two before they get sold and consumed.
That’s why you need to cellar them for a few months to get that glinty aluminum taste 
Any chance they came from different breweries? I don’t know how Miller is brewed, but Bud and Coors are brewed in multiple locations.