On Tuesday night Strasbourg's hotels were booked solid and journalists spilled out of the press room, where the desk space had long since run out. At one point, a message crackled over a taxi's two-way system: there were no cars free anywhere in the city.
Not so long ago, the European Parliament was regarded as little more than a joke by the Brussels elite. Then came the pyrotechnics of March when, under pressure from MEPs, all 20 European Commissioners were forced to resign over allegations of sleaze, cronyism and mismanagement.
Some saw this as a new dawn and a historic confrontation between Europe's parliament and its executive, but an equal number viewed it as a publicity stunt ahead of June's European election. And lately the parliament has shot itself spectacularly in the foot. First it rejected the opportunity to clean up the ludicrous regime of expenses for MEPs, under which lavish payments can be claimed for travel without so much as a receipt. Then its politicians conducted a lacklustre election campaign across the Continent that brought less than half of Europe's voters to the polling booths.
Last week it crowned its reputation for folly with a move into a new, universally ridiculed pounds 250m building in Strasbourg. A day of high French farce ensued with faxes arriving at the offices of political adversaries and one assistant being trapped for hours in a lift. Marooned in her minute office, one MEP complained bitterly of being blinded by the glare from the glass of the ultra-modern adjacent building. Against the odds, however, the journalists and lobbyists who swamped Strasbourg were not disappointed. Despite the aesthetics of its new debating chamber (described by one legislator as having all the gravitas of the starship Enterprise), the European Parliament served up a political event of genuine importance.
On Wednesday Romano Prodi, the incoming president of the European Commission, presented his 19 Commissioners in the first step of an elaborate process including hearings to vet individuals, and culminating in a vote on 15 September. At that point parliamentarians will be asked to endorse the Commission and, should they decline, Europe will face a second political catastrophe.
Mr Prodi's speech combined populist initiatives with carefully pitched flattery of the parliament. He was flanked by his new team, which included Germany's former minister for Europe, Gunther Verheugen; the former Governor of Hong Kong, Chris Patten; and Pascal Lamy, one-time aide to Jacques Delors, the legendary former Commission president. Mr Prodi and his Italian colleague, Mario Monti, possess notable intellects. And Neil Kinnock's record as a political reformer is in no doubt.
Yet MEPs were in no mood to roll over and have their tummies tickled. Hans-Gert Pottering, chairman of the centre-right European people's party which dominates the parliament, warned bluntly: "We remain perfectly free to say yes or no to the Commission. We may decide not to give our approval to the Commission."
Does this point to another European crisis in the autumn? If nothing else, it reflects a new, messy political climate in Europe, one that provides the framework for a political trial of strength.
Last year, in the wake of changes of government in Germany and Italy, the left ruled supreme with control of 11 out of the 15 member states, including all the big nations bar Spain. This political hegemony was reflected in the European Parliament, where the socialists formed the biggest block. But June's European elections delivered a series of humiliating reverses to the left, particularly in Britain and Germany, where opposition parties made big gains. With the centre right now installed as the biggest force in the parliament, Strasbourg is firmly at odds with the governments of member states.
It is national capitals that nominate European Commissioners, subject to the approval of Mr Prodi. And the refusal of Gerhard Schroder, the German Chancellor, to let the centre right have one of Germany's two Commissioner posts points to a conflict over the approval of Commissioners. It also points to a wider dispute over the new balance of power between left and right in Europe.
Strasbourg has become the obvious cockpit of this ideological debate, at a time when the self-confidence of MEPs is growing. The new parliament has 23 new areas of "co-decision", under which it now plays a crucial role in legislation affecting transport, employment, development and public health. The calibre of MEPs is improving. Accomplished committee chairmen include Elmar Brok from the German centre right, while the leader of the Liberals, Pat Cox from Ireland, has established himself as an impressive performer.
A new, younger breed of politician sees Strasbourg - rather than domestic politics - as a route to political influence. That even applies to Britain, where the calibre of the new Liberal Democrat MEPs is higher than that of many of their colleagues who were elected to Westminster for the first time two years ago. Despite its many flaws, the European Parliament has gained in power, and it has tasted blood. Mr Prodi knows that things can never be the same again.