I have this same issue with WebEx meeting invites showing up wrong in iCal. On other calendar programs the same WebEx invites are set to the correct times. The problem is definitely related to the recent switch from Standard time to Daylight Savings time. iCal does not switch the invite to Daylight Savings time and instead still interprets it as being at Standard time (thus the one hour difference in the time on your calendar).
After looking at the text of the WebEx invites and invite files from other meetings, I found you can manually fix invites by editing the .ics files.
If you remove ";BYHOUR=2" from the two RRULE lines in invite files (similar to the two RRULE lines in the above invite text example), the invite will show up in iCal correctly and it still shows up correctly on other calendar programs too. Perhaps iCal handles this argument incorrectly or maybe WebEx is not using it correctly, but since these invites appear correctly in other calendar programs, I think the problem lies with iCal.
You can test this by opening the invite (.ics) files in TextEdit, then removing this setting in the two locations, and then using Save... to resave your invite file. Make sure to keep a .ics file extension. Opening the invite in iCal should allow it to show up correctly.