For a start, it has become a money-raising machine, not yet caught up with the mighty Conservatives in terms of dollars, but "in the same ballpark now," as one insider put it.
The convention follows the most radical change for any Canadian political party since the merger of the Reform and Canadian Alliance parties — the ditching of the more than 100-year-old tradition of Liberal senators.
In Justin Trudeau it has a leader steadily leading the polls while not being immune to controversy. At the moment he is facing scrutiny over his choice of adviser, as questions are raised about retired lieutenant-general Andrew Leslie's moving expenses.
All this change has occurred after a series of disastrous years, internecine warfare, failed leaders and historic seat losses. After the last election, many wondered if the Liberal Party would soon disappear, just as its British counterpart — the once-great institution that produced William Gladstone and David Lloyd George — had faded into insignificance.
Colossal defeat in 2011
After the near-death experience of 2011 that reduced the party to 34 seats and saw its leader, Michael Ignatieff, lose his own riding, the sense of hitting bottom prompted an imperative to evolve or risk extinction.
"We learned an important lesson during the 2011 campaign, that doing things the traditional way was not working," said a Liberal staffer.
The convention beginning today and running through the weekend is expected to provide a sense of invigoration and self-reinvention.
Some resolutions, if they pass the plenary sessions, will brand the Liberals as progressive or dangerously radical, depending on your point of view, as did the previous convention's 75 per cent endorsement of legalizing pot.
The resolution about medically assisted death will be closely watched. So will one on an electoral system based on proportional representation. Scott Simms, the Liberal democratic reform critic, in a phone interview, said, "Not everyone agrees with it, but we want to get it out there to see the temperature in the room."
But mostly the convention will try to be about showing new — and mostly younger — faces. The circle around Trudeau is largely 40-something at the most, reaching back into mid-30s.
This is the middle class Trudeau wants to speak to, along with the youth sector of the electorate that doesn't vote, a group whose age skews up to 45.
To capture them, in particular, the Liberals are embracing the get-out-the-vote methods of advanced data analytics. It's the art of finding pools of persuadable voters and trying to influence their circle of friends to urge them to vote for you, through social media and finely researched targeted messaging.
It is also something the Conservatives have become very good at.
To that end, two of the keynote speakers for the convention are managers from the Obama campaigns.
One of those is the millennial digital guru Teddy Goff. Not yet 30, Goff was director of Barack Obama's digital strategy in 2012, and ran a voter outreach program credited with helping him win re-election.
Stories the Liberals don't want
Yet for all the emphasis on new faces and new technology, the convention may be dominated by stories the Liberals would rather not be the focus.
Some former Liberal senators — older faces, a bit like ghosts of the Liberal past — will show up, despite their leader's exhortation that he wants an independent non-partisan Senate. But under party rules that have yet to be amended, a handful will be there, some as ex-officio delegates automatically registered and able to vote.
The Toronto Star has reported that Conservative infiltrators will be taking pictures of the senators as they enter the convention to counter Trudeau's claim there are no more Liberal senators.
The other story that will bubble up is Leslie's $72,000 tab, picked up by taxpayers, for moving from one house to another in the same Ottawa neighbourhood after he retired. Leslie, who already has a shadow campaign team in place for a run in the riding of Ottawa-Orleans, is a keynote speaker at the convention.
Leslie is touted as a possible part of Trudeau's star-candidate roster, one that includes new MP Chrystia Freeland, who will be appearing at the convention with Lawrence Summers, the former head of the White House National Economic Council.
But Leslie will be dogged by media questions about his expenses, and former senators will be pursued by reporters over their status as Liberals. Both those issues may cast a bit of a pall over what is meant to be a celebration of how far the party has come from what it was.