Show me some proof that users of Open Office got full legal protection for any illegal intellectual property that may be in the product, and that the liability didn't transfer to them instead. Read the GPL license, it explicitly says "no warranty".
Read the MS Eula:
11. LIMITED WARRANTY FOR PRODUCT ACQUIRED IN THE US AND CANADA.Hmm. Sounds like the only warranty MS gives is that mandated by law, due to its monopoly status.Microsoft warrants that the Product will perform substantially in accordance with the accompanying materials for a period of ninety days from the date of receipt.
If an implied warranty or condition is created by your state/jurisdiction and federal or state/provincial law prohibits disclaimer of it, you also have an implied warranty or condition, BUT ONLY AS TO DEFECTS DISCOVERED DURING THE PERIOD OF THIS LIMITED WARRANTY (NINETY DAYS).
AS TO ANY DEFECTS DISCOVERED AFTER THE NINETY (90) DAY PERIOD, THERE IS NO WARRANTY OR CONDITION OF ANY KIND.
Some states/jurisdictions do not allow limitations on how long an implied warranty or condition lasts, so the above limitation may not apply to you.
Any supplements or updates to the Product, including without limitation, any (if any) service packs or hot fixes provided to you after the expiration of the ninety day Limited Warranty period are not covered by any warranty or condition, express, implied or statutory.
LIMITATION ON REMEDIES; NO CONSEQUENTIAL OR OTHER DAMAGES.
Your exclusive remedy for any breach of this Limited Warranty is as set forth below.
Except for any refund elected by Microsoft, YOU ARE NOT ENTITLED TO ANY DAMAGES, INCLUDING BUT NOT LIMITED TO CONSEQUENTIAL DAMAGES, if the Product does not meet Microsoft's Limited Warranty, and, to the maximum extent allowed by applicable law, even if any remedy fails of its essential purpose.
If you really want to compare the GPL and MS' Eula, I'd suggest this analysis in PDF format.