If you call yourself a webdesigner and cannot wrtite a page in pure HTML/CSS by hand, you lie. Period.
While this sounds harsh, its actually obvious: you need to know whats possible and how complex it is to implement what you design.

Yes, what you design looks good, but there is a reason that you've never seen tilted text with a drop shadow and a gradient on a website.

Yes, you can slice your psd and it will display in your browser, so obviously it is possible to implement what you design?
really? Think about it...
just look at the "code" you generate with this method.
And ever thought of *dynamic* content being displayed? And no, I won't constuct an image and slice it on the server side..

Heck, do you realize what evil hacks are necessary just to get the rounded borders on this page? Tons and tons of clientside Javascript render these. Yes, on the client. Yes, on every pageview. No, there is no compatible way of doing this with HTML/CSS until all browsers out there know CSS3.
Billions of billions of billions lines of Javascript get interpreted by home computers every day, wasting energy and computing time just because you guys want rounded borders and did not know how complex this is to implement.

If you feel adressed by this text: You may call yourself designer, but please dont call yourself webdesigner. You'll lie to yourself, to your customer, and that poor little bastard who'll have to translate your .psd into HTML/css will curse you, use evil hacks, will get blamed for things not working and taking too long. He might kill you.

Real webdesigners know what's possible and work with what they have. Sadly this is practically limited to HTML4 und CSS2, but things will soon get better with HTML5 and CSS3.