Let's start with the sopranos. From English mezzo Susan Bickley in the opening concert performances of Weill's Rise and Fall of the City of Mahagonny to double Bank of Scotland Herald Angel-winner Jane Irwin in Tippett's A Child of Our Time, 2008's Edinburgh International Festival has a line-up of top sirens to lure the most discerning listener.

Anne Sophie von Otter will be appearing with William Christie's baroque group Les Arts Florissants. Karita Mattila performs Tatiana's Letter Scene from Eugene Onegin with the Finnish Radio Symphony Orchestra under Sakari Oramo. Katharine Fuge will be singing Brahms's German Requiem with Sir John Eliot Gardiner's Monteverdi Choir. Angela Denoke appears alongside alto Karen Cargill in Honegger's Le Roi David. Lucy Crowe and Claire Debono sing Handel's Israel in Egypt with the SCO under Emmanuel Haim. Kate Valentine and Jane Irwin are The Two Widows in Smetana's opera that marks the Festival debut of Scottish Opera's new music director, Francesco Corti. The Queen's Hall series includes the Festival debut of Sandra Bullock as well as enticing recitals by Christine Schafer, Katarina Karneus and Christiane Oelze.

That's far from all the ladies, and the gentlemen range from countertenor Robin Blaze to the top baritone of our time, Dmitri Hvorostovsky. Connoisseurs of voices will be forced to make choices between August 8 and 31.

That list is only one aspect of the second programme from director Jonathan Mills, but it will reassure many long-term festivalgoers still unsure of the new man - and damns criticism that greeted his appointment in some quarters. The target of a scurrillous personal attack from a now discredited blowhard when he got the job, Mills served up a first festival that rung the changes in many ways, with an entirely new cast of theatremakers and a brave concentration on early music in a vast programme at Greyfriars Church. Year two shows further development in some areas, but also displays a reluctance to repeat himself that he shares with his predecessor, Sir Brian McMaster.

So, as the list above suggests, some of that early music has made the transition to the much larger space of the Usher Hall, but Greyfriars Kirk has not been entirely forgotten. There, a five-concert Song and Civilization series links the music programme with the theatre programme by showcasing the choral traditions of Europe and the Middle East.

Unlike McMaster, Mills is keen to make clear that his festival is a curated event. EIF' 08 has a title - Artists Without Borders - and, contrary to the rumours that suggested the Australian would shift the focus in Edinburgh to the Pacific rim, is concerned with the expansion of the European Union and the diversity of a continent that stretches from Estonia to Cyprus and beyond.

This goes so directly to the heart of what the Edinburgh International Festival was created for in the years following the Second World War that it hardly needs stating. When geopolitical boundaries are being redrawn in every direction, it is right and proper that artists are in the front line and Poland, Iran, Palestine, Bosnia, Israel, Turkey and Georgia are all represented in Mills's dance and drama programme.

The Polish presence is substantial, including a staging of Sarah Kane's acclaimed last play, 4.48 Psychosis, and Jewish folk classic The Dybbuk with top Polish cinema actors. Opera Wroclawska's production of Szymanowski's King Roger is revived by Valery Gergiev's Mariinsky Opera as the centrepiece of a remarkable residency that also sees the maestro direct his other band, the London Symphony Orchestra, in performances of all seven symphonies of Prokofiev. Only those with very long festival memories will be able to remember a London orchestra making a temporary home in Edinburgh in August in that way.

One of Mills's concessions to the artistic achievement of his homeland is in the return of director Barrie Kosky, who brings with him performer Martin Niedermair from last year's Poppea in an adaptation of Edgar Allan Poe's The Tell-Tale Heart. Besides Kane, the other British writers in the drama programme are Nigel Williams, whose radical 1970s play Class Enemy is translated to Sarajevo by East West Theatre Company and David Harrower, whose new play for the National Theatre of Scotland, 365 - One Night to Learn a Lifetime, is about a practice flat, designed to help children in care make the transition to independence.

The dance programme ranges from Georgia Ballet's Giselle to the Whirling Dervishes of Turkey and Australia's Chunky Move. As well as the premiere of a new Matthew Bourne piece based on Oscar Wilde's Picture of Dorian Gray, there are the Edinburgh Festival debuts of Israel's Batsheva Dance Company and Anne Teresa de Keersmaeker's Rosas company, performing the whole of her repertoire to the music of Steve Reich.

Lovers of contemporary classical performance will also be delighted by the return of Heiner Goebbels, whose Black on White, Hashirigaki, Eislermaterial and Eraritjaritjaka were highlights of the McMaster era and whose I Went to a House But Did Not Enter features the vocals of the Hilliard Ensemble. Also continuing the thread of programming pre-Mills is the final festival concert by pianist Alfred Brendel, who is retiring from the concert stage. Tickets for that are sure to be like gold dust, and you'll have to be fast to secure tickets for the return of Ivan Fischer and the Budapest Festival Orchestra, a sensation (and Herald Angel winners) back in 1997.

Another distinguishing feature of this year's event is a commitment to the use of the Hub, the EIF's Ben Tindall-designed (and Angel-garlanded) home at the top of the Royal Mile. In past years it has had mixed fortunes as a venue, but Mills has programmed it with daytime conversations, late-night music performances, a film installation of a Persian passion play, the Bazi theatre company's all-female Devil Ship and Germany's Muziektheater Transparant working with Collegium Vocale Gent. From being a mere box office, the converted church looks set to live up to its name for the first time.