Despite party membership increasing, Corbyn's Labour Party reached a new low this week, losing its deposit at the Richmond by-election.
Although its a one off and these things dont decide the make up of the next parliament, for the main opposition party to suffer such a low share of the vote is quite unbelievable.
Of course, the Libdems threw everything, including the kitchen sink, at this one but, Labour appear to be facing political oblivion.
UKIP are taking increasingly large chunks of Labours traditional support (although not in this particular seat) and with Scotland now solidly SNP, how can Labour ever expect to take power in Westminster in the future.

No!

Next question

So a by election when the party in power arent exactly popular and the main opposition party loses it's deposit, it's not exactly good news, for Corbyn, is it ?

It was Richmond

The most affluent constituency in the country? What were you expecting?

Labour voters voted tactically for the Lib Dems, in order to reduce the Tory majority. This is not reflective of the troubles of the Labour party, but of the stupidity of our first past the post electoral system.

Time will tell.
Obviously Labour were never, in a million years, going to win this seat and I fully accept that.
However, whilst Corbyn is clearly very popular among Labour activists, for the population at large, he has a similar "draw" as a certain, Michael Foot and it looks very much like they (Labour) face a similar length of time in the political wilderness.
Indeed, with Scotland now ruled by the SNP, it's quite possible that we may never again see a Labour government in the UK.
At the moment, they dont even come under the title of effective opposition which, isnt good for anyone.

I'm not questioning the argument that Corbyn is not looking electorally ineffective, more just that I don't think Richmond Park is anything to do with that. The argument around Corbyn is often that what appeals to the members (which he clearly does) doesn't appeal to the electorate. However, there's actually more Labour members in Richmond Park than voted Labour there in the by-election, which is why I'm so convinced it was overwhelmingly tactical voting rather than anything else.

At one point Labour were considering not fielding a candidate to give the Lib Dems a better chance but caved in to the local members demands that they should have the option to vote for their own party.

Corbyn's politics are a sort of student union' left-wing populism, it's based on a sort of "the enemy of my enemy" schtick, so for example he can get over people actually being murderous terrorists or anti-semites or any number of harmful things as long as they self-identify as opposing ideological concept he also opposes e.g. "American imperialism" or "Neoliberalism". It is in many ways the opposite of "small c" conservative pragmatism, because the actual harm done by these "friends" is considered less than the conceptual harm that can be attributed to the "enemy ideologies". The purity of the ideology is more important than the physical manifestation, so fare example stuff should be nationalised on principle even if the actual result would be no better or possibly even worse. This plays well with a substantial minority, but the majority, including the realist "left" which most of the Parliamentary Labour Party belong to, know its juvenile rubbish and the "real world" is more complex.

Corbyn won't be the end of the Labour Party, he's got to be given a chance to fail and hope that a new (pre-Iraq War) Blair figure can be found, who can put forward a sensible platform to rebuild on. It must be remembered that hard Left "Corbynistas" need the Labour brand, there are any number of socialist factions who've going nowhere slowly for a long time with the same schtick.