I created an iCal file that went from 100% to http://icalvalid.cloudapp.net . I send an iical file with mimetype text / calendar to my gmail account and I observe 3 different moments when I send a meeting request from the yahoo calendar:
First, the "View on Google Calendar" link is broken, the URL is http://www.google.com/calendar/undefined .
Secondly, I do not get Yes | No | Maybe buttons, but instead, the Add to Calendar link
Invitation:

My App Invitation:

Thirdly, when I actually open an event in Google Calendar, I see the source field for yahoo events, but I do not understand this:

ics , .
, :
BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//MyCompany//MyApp//EN
METHOD:PUBLISH
BEGIN:VEVENT
SUMMARY:this is the summary
DTSTART;VALUE=DATE-TIME:20140504T120000
DTEND;VALUE=DATE-TIME:20140504T140000
DTSTAMP;VALUE=DATE-TIME:20140514T095627Z
UID:58cf4653e9da4fbaa27fbef1e9815d95@myapp.com
SEQUENCE:0
CLASS:PUBLIC
DESCRIPTION:this is the description
ORGANIZER;CN="My App";ROLE=CHAIR:MAILTO:me@myapp.com
PRIORITY:5
STATUS:CONFIRMED
TRANSP:TRANSPARENT
END:VEVENT
END:VCALENDAR
, :
- " Google"?
- gmail Yes Maybe No?
- ?
, 3 - , Google .
- !