Grandprix.com brought up some interesting points in the following article

汗..百度有抽了

Scuderia Toro Rosso has been working to try to conclude a deal that will allow it to announce on Wednesday that multiple Champ Car champion Sebastien Bourdais has reached agreement to join the team in 2008 and will therefore team up with Sebastian Vettel. The news will not be a surprise as there was never much hope that Tonio Liuzzi was going to stay with the troubled Italian team.It remains to be seen what happens to Liuzzi but there is no doubt that his relationship with Red Bull in F1 will be finished at the end of the season - if not before. For a team that is changing two drivers, it makes a lot of sense to get them into the cars as soon as possible. That has been done with Sebastian Vettel and it makes sense to do the same thing with Sebastien Bourdais, indeed it makes more sense in his case, as he needs more time in F1 cars than does the German. An early split also makes sense for Liuzzi as he could then be available to try out with other teams, some of which might even want to change drivers before the end of the year, for the same reasons as Toro Rosso.

Much depends on whether Bourdais is available. His Newman-Haas contract allows for F1 testing and he could do most of the remaining F1 races because the dates do not clash but, unless there are specific clauses in the contract to cover such things, Carl Haas is going to want to be paid and Scuderia Toro Rosso may not want to pay.Despite all the adversity Liuzzi has managed to retain a decent reputation in some F1 circles. Every now and then, when it is possible, he has shown his pace but most of the time his talents have been hidden by the machinery. When he came into F1 back in 2004 he was in the running for the Sauber drive instead of Jacques Villeneuve, but since then Red Bull's handling of his career has not been very impressive. In 2005 he had to share a car with Austria's Christian Klien because the drinks company was worried about negative publicity in Austria if it dumped Klien. Liuzzi impressed, scoring his maiden point on his debut, but was then pushed into the role of test driver when it became clear that sharing the car was a daft idea. At the end of that year Red Bull acquired Minardi and changed its name to Scuderia Toro Rosso. Once again Red Bull was fixated on the Austrian media and Klien was retained (although he was ousted before the end of the year) and so Liuzzi was pushed back into Toro Rosso. He scored the team's first point in Indianapolis but the team management then began to blame the drivers for most of the failures and the current problems began.