Long overdue departure. Bring on Ricciardo! 
Ricciardo is more consistent than Vergne but could be like Webber's consistency, consistently 4th. Vergne is not consistent, is not a good qualifier, but to date has had better race results despite starting further back.
If Ricciardo can capitalise on his good qualifying result this weekend, then that could well improve his value and make him the favourite for the seat.
I have a bit of a bitter pill about Webber's retirement. I wouldn't say it's long overdue, as the timing of his departure has coincided with an above-average Toro Rosso car. If he had retired earlier, we could've been in a bit of a pickle, although maybe Alguersuari would still be racing....
But the way how Webber resigned, giving his team only 1 hour's notice just continues with Webbers consistently up-himself arrogance to the team. He has been extremely unprofessional at times over the past few seasons, and I am actually looking forward to the end of Vettel's partnership with him, which has been so strained.... (Of course, I acknowledge that Vettel has also been unprofessional at times).
Now Vettel can get a team mate who won't be consistently fighting against the grain. They will hopefully respect Vettel. (Not saying that they are expected to be slow) but there can now be an undisputed number 1 and 2 driver.
Ideally his new team mate will hopefully do a better job at finishing second when Vettel wins, or winning when Vettel is out. Webber has failed at this, and whilst I acknowledge his contribution to Red Bull's championships - I think he could have still done a better job at being a rear gunner.
Unfortunately I will only remember Webber for his constant complaining, his 1 win against his team mate's 11 in the the 2011 season, and "everyone is against me mentality."
The perfect team mate relationship is happening at Mercedes. I think Hamilton/Rosberg and Button/Hamilton epitomise the perfect example of a quick driver pairing who are also team players who respect each other.