I'd say when done right, with carefully picked spells takeing others and future levels into acount, a sorcerer is the definate winner in power. And with the right spells a sorcerer can have some nice abilites. With invisibilty they can disapeer almost any time they feel, with fly they can get anywhere they need and not get stuck up that ledge because the spell ran out and they only had one prepared. its all about picking spell that have good potential for repeated use.
A lot of the pro-wizard reasons here such as wands and scrolls are very money/xp heavy. You would have to asume that the sorcerer has the same amount to spend on any other gear. And there is plenty of nice items in the dms guide alone. They may be less suited to preparing a libary of scrolls, but with a few well picked purchased scrolls they can still have plenty of tricks up their sleeve.
Plus wizards, unless they have incredibly good intel on what they will need, very often end up coming back with spells left over which they didn't need. Even good preperation can turn out bad, when they come across an unexpected twist. Wizards advantages require time out of the field, or to retreat so they can come back tomorow with the 'get past puzzle' spell prepared. In some situations that option just isn't availible.
I would say that sorcerers skills are terible, wizards have int to boost theirs, while sorcerers are tipicaly left with a measly 2 or 3 points per level. I have free eschew matierials as a house rule. How the hell can you have inate natural powers that require you to be convinently holding some bat dung at the time? (fireball)
Conclusion, I like both...
As a Socerer I've grined as deal out non stop death, but also been irritated that I shouldn't pick that spell I'd like as I know I'd barely use it. As a wizard I've enjoyed haveing a solution to everything, but had the problem of never haveing the solution to everything when I realy need it.
... but the sorcerer is the clear winner in terms of 'power'.