At last August's V96, the festival which saw Britpop's stars squeeze one final performance out of their 1995 albums before returning to their recording studios/going on holiday, Supergrass and Elastica sounded unsure of their identities. They offered a couple of new songs, none of which quite fitted in with their previous output.

Cast, on the other hand, had no such problems. They were, as always, Paul Weller's kid brothers, an old-fashioned beat group. With a knack for finding a singalong hook and writing primary-school self-improvement lyrics - all "you've gotta" and "I wanna" - John Power achieves naively and earnestly what the likes of Stock, Aitken and Waterman used to do while rubbing their calculators in glee.

However, what's good news for a summer afternoon's open-air entertainment is not so good for a continuing, challenging career. The reason Cast knew where they stood was that they weren't moving on. They were typecast. Sure enough, their sophomore album, Mother Nature Calls (Polydor) turned out to be as surprising as a bar of soap. And, on Tuesday, in the giant gym hall that is the Plymouth Pavilions Arena, you wouldn't have known that time had passed since V96 at all, were it not for John Power letting his curly hair grow, so that he resembled one of Harry Enfield's Scousers even more (as if chirping, "I just wanna be dinkin' doughts dat I dink," weren't Enfieldian enough).

Hearing the pub-rock riffs of Mother Nature Calls live, without the studio effects which John Leckie valiantly contributes, it's hard to get too excited about Cast. Mind you, their all-round ordinariness accounts for much of their appeal. Every one of the thousands of boys present in Adidas trainers and untucked button-down shirts looked as if he could have been a member. (And, who knows, any one of the crowd might have matched the band's performance abilities.) More than once I wondered if Cast weren't a ploy by Oasis's spin doctors to make the Gallaghers seem extraordinary.

It's not the wearisome psychedelic jamming on "History" that will convince the doubters (ie, me) that the group are worth their record sales, nor is it the shower of balloons, nor the giant ping-pong balls decorating the stage. Instead, it's a few more songs like the propulsive "Fine Time", or the maximum R&B of "Alright". It's on these that Power's talent really takes flight.

More deserving of your money are Catatonia, a newish Welsh band, who nonetheless fail to dress up as wizards or impersonate Syd Barrett. On Wednesday they were in the Portsmouth Wedgewood Rooms, playing material from last year's debut, Way Beyond Blue (Blanco Y Negro) - and what material it is. From the twinkling pop of "You've Got a Lot to Answer For" to majestic torch songs like "Do You Believe in Me?", Catatonia specialise in wide- open melodies and grunge dynamics, while the crashing waves of minor chords, Radiohead-style, are even more dramatic onstage than they are on vinyl.

I couldn't say what the lyrics are about, exactly, but it's plain that they're peppered with smart, memorable phrases, written by the brassy Cerys Matthews. She flings herself into the songs, and, when she's not swigging from a lager bottle, she's releasing a gush of girlish, emphatic vocals, like Bjork's, but with a hoarse, sexy edge.

So: Bjork fronting a poppier Radiohead. The only question is why they aren't famous yet. One reason may be that Catatonia's name would persuade a browser that they were an adolescent doom-metal band. Another may be their utter absence of style: Matthews has her hair pinned up messily, and wears gold necklaces over her white T-shirt, as if she'd planned to spend the evening serving tea on EastEnders. If you've ever chuckled over one of those embarrassing early photographs of Suede or U2 before they sorted out their image, you'll know what Catatonia look like now. With a quick makeover, a level of success similar to these other bands' may be in the pipeline.

On the new album by Edward Ball, Catholic Guilt (Creation), he makes 10 stabs at rewriting the Kinks' "Waterloo Sunset". If our hypothetical browser heard these wistful Londoner's confessions, she would guess that Ball was a clever, very English post-punk singer-songwriter, with a long and fairly illustrious chart career behind him. Someone along the lines of Elvis Costello, perhaps, or Nick Lowe or Ian Broudie ("The Mill Hill Self Hate Club", his best pop song by far, sounds like a less saccharine Lightning Seeds). She'd be right, more or less, except for the bit about the past career. Ball has done his time in various forgotten indie bands, and has served as an associate member of the Boo Radleys, but none of these have made his name. This year, promise Creation Records' press office, will be different. Ball will "appear on Top of the Pops, headline his own tours and receive gold records". He once helped to run the company, so they were happy to get Anna Friel to star in one of his videos, and thereby guarantee him an appearance on The Chart Show. Top of the Pops might be more tricky.

At a low-key show at London's Borderline Club on Thursday, he proved to be an extremely likeable fellow, with a self-deprecating enthusiasm which suggested that he'd be as surprised as anyone if the hype came true. He has little cause for alarm. He is now on the wrong side of 30, and only just on the right side of 40, and he wouldn't quite have the looks for pop stardom even if he weren't so defiantly bald. (In "Trailblaze" he pastiches the Beatles: "I woke up, fell out of bed/ Dragged a razor across my head.") Live, his singing was weak and not always in tune, and the skilled band sounded thin and short of spark. So, no illustrious pop past or future, but Ball could yet wheedle his way into the esteemed English cult songwriters club, which is probably where he belongs.

Cast: Portsmouth Guildhall (01705 824355), tonight; Reading Rivermead (01734 504343), Tues; Cambridge Corn Exchange (01223 357851), Wed; Sheffield City Hall (0114 273 5295), Thurs.