I imagine it will be a while before anyone at Citroen is prepared to say this without insisting on anonymity, but it strikes me that the new C3's launch date of 15 January 2010 won't be a moment too soon. The current C3, now well into the coughing-up-blood stage, appeared in 2002, and it wasn't much cop even back then. In particular it felt very cheap indeed, and its design, described by Citroen at the time as "friendly-looking, distinctive and stylish", made it look, to me at least, like a trilobite.

The new C3, which is almost exactly the same size as a Ford Fiesta, feels like the work of a company which is at its ease with larger and more luxurious cars. It's not quite as impressive in that respect as the Fiesta, or indeed the Volkswagen Polo, but it is certainly a major improvement (or a "huge leap" - Citroen's words again) over what has gone before. And it looks nothing whatever like a trilobite.

It does, however, look slightly odd, in all forms other than the entry-level VT. That version has a conventional windscreen, whereas the others (VTR+, Exclusive and the special edition Airdream+ I'll be dealing with shortly) have what Citroen describes as a Panoramic Zenith screen, which extends beyond the heads of the front passengers. You probably didn't know, and I didn't either, that the average angle from the driver's eyeline to the top of the screen in a supermini is 28 degrees. Well, with the Panoramic Zenith, it's 108 degrees.

If you drive in constant fear that somebody may be about to drop a grand piano on you from a tenth-storey window, the C3 is the supermini for you, since you can check whether or not this is going to happen simply by glancing upwards. Personally, I'm rather casual, perhaps wrongly, about assaults of this nature, and that's one reason I'm not a great fan of the Panoramic Zenith. Another is that I can't help wondering how much it would cost to replace the screen if it were to be irreparably harmed (which could happen - I mean, even a piccolo is going to do a lot of damage from ten storeys up).

A third is that the screen makes the C3 look as if it has a bad case of receding hairline, and a fourth is that I don't like having all that glass around me because it makes me feel vulnerable. There's no good reason for that. It just does, and I don't like it. Fortunately, if you are likewise minded, you can block out most of the glass by pulling a cover across it, which is what I would do every time.

I would also, without hesitation, buy a diesel C3 rather than a petrol one. That's not just because the diesels are more economical, are cheaper to tax thanks to their lower CO2 emissions and have better mid-range performance, but also because the ride is so much better. From my brief experience so far, the petrol cars are just too bouncy, whereas the diesels feel a lot more secure even when you're just pottering around town.

All the same, even the diesel C3 hatchbacks are not quite as splendid to drive as their Picasso mini-MPV equivalents, which I find very strange indeed. The Picasso is also a lot more practical, of course, though the hatch has a very useful load capacity of 300 litres with all the seats in place. That's 200 less than the Picasso, but very good for a supermini; in fact Citroen says it's class-leading, which is true, though it's only five litres more than the Fiesta and the Hyundai i20 provide.

There is a lot of room for front passengers too, as there was in the old C3, but rear legroom is limited to the extent that four six-foot adults would find it difficult to get comfortable. Bearing in mind how superminis are generally used, though, I doubt that many customers are going to wail and gnash their teeth over this.

Your local Citroen dealer will be able to talk you through the differences between the trim levels, but a couple of points are worth mentioning here. All versions except the VT get air-conditioning as standard, and all except the Exclusive have full-sized spare wheels (the Exclusive gets a space-saver, but at least it's not one of those daft repair kits which are no use to man nor beast). The Exclusive also stands alone in that it's the only one available with rear electric windows, and the only one supplied - optionally, at extra cost - with ESP, which has dropped it from a possible five stars to just four in the Euro NCAP crash test ratings.

The Airdream+, which comes only with the 90bhp 1.6-litre turbo diesel engine, has more or less the same equipment as the mid-range VTR+, apart from having steel wheels rather than alloys, but it's special in that it has by far the best combined fuel economy of the range at 74.3mpg (even the less powerful 1.4 diesel is more than 8mpg shy of this) and is exempt from VED thanks to official CO2 emissions of 99g/km. At £14,490 it's more than halfway up the price list, though, and like the cheapest (1.1 petrol VT, £10,790) and most expensive (1.6 HDi 110bhp Exclusive, £16,140) and the only automatic (1.6 petrol 120bhp Exclusive, £15,590) it won't go into production until March, two months after the rest of the range has started appearing in UK showrooms.