This is obviously in Brent rather than Ealing but close enough for it to have some relevance.
The Lib Dems have overturned a big Labour majority in Alperton. Obviously by-elections can be misleading but I'd be surprised if the Lib Dems aren't seeing this as hugely significant. Up until now in Ealing they have been nibbling away at Conservative wards to establish themselves as the main opposition. This limited objective having been achieved they seem content to stick never really giving the impression that they could win wards in Labour strongholds. This seems to be questionable now and with only 15 months until the next full election, if they got their act together, they could pull off a major surprise.