The intrepid folks over at XDA are always tinkering away to try and make using your Android device a better experience. And a few weeks ago, one of them (namely, temasek) found that the Android Market has some issues trying to resolve DNS servers when your device is connected over Wi-Fi. This can cause the Market to load slowly, and it's definitely something I've experienced on my own phone.
The solution? A popular app called Set DNS (note: root is required), which forces your phone or tablet to use a particular name server when connecting to the web, may speed up load times over Wi-Fi. Upon using it myself, after a reboot, I noticed the Market did seem to load substantially faster than I've grown accustomed to. Here's the link to the free version:
This version does expire, so if you want to keep using it, you'll have to cough up a quid (1GBP or about ~$1.70US).
You can use any of the DNS services the app offers, though OpenDNS has always been my preferred DNS service. Has this sped up your Market load times on Wi-Fi? Let us know in the comments.