Hello,
You will find that this a common issue (search the forum for "keyboard flex"). Depending on whether you've owned other Thinkpads, you may or may not consider this an issue. My previous Thinkpads (R32 and T42p) had excellent keyboards, so the flex in W500 was unacceptable to me. Here is my (positive) experience with Lenovo customer service, as posted on the "other" Thinkpad forum:
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My dealing with Lenovo Canada on the keybord flex went smoothly. When I received my W500 on June 26, the flex on the left side was obvious. I called Lenovo right away, but my system was not yet showing up in warrantly lookup. They took down all my information and requested that I fax them my proof of purchase in order to proceed. I am still waiting for the invoice to arrive in the mail. However, I kept checkign the online warranty lookup, and the moment my system showed up I gave Lenovo a call. The conversation went something like this:
Me: I have significant flex on the left side of my keyboard. From Lenovo support forum, I understand that Lenovo is aware of this issue and is issuing free keyboard replacements, using older model keyboards from T61 series. I have the FRU for it.
Rep: Yes, I have heard of this, but I am not sure if this is a warranty issue. Let me check with my manager.
Me: Of course, please do. (I am on hold for about a minute).
Rep: OK, you said you have the FRU for the keyboard.
Me: Yes, it's 42T3143, and there are 2 more that replace it for T61 series.
Rep: Yes, that seems like it would work. We have them in stock. Let me put in an order for it. (I am on hold for about a minute) You are all set up, you should get it in a few days.
Me: Thank you very much.
I got the keyboard today and just swapped it in. What a difference! It feels almost as nice as my T42p

! No flex and the key sound is consistent across all the keys.
I have compared the keyboards before installing the replacement, and it is immediately obvious that the the old keyboard is of much superior quality.
Wishing all the other W500 buyers to have as smooth an experience with the keyboard replacement as I did.
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