Not all browsers are created equal and websites don’t always look 100% across the browsers. Internet Explorer specifically is an inferior browser however it’s usage share is currently only 18% and declining. Here is a link that will show the world wide usage: http://www.w3schools.com/browsers/browsers_stats.asp
First of all for creating a website that looks consistently across the browsers, the HTML and CSS code need to be properly written. Here is a link that validates the HTML :
http://validator.w3.org/. If the page is full of errors the website was poorly coded. Not all errors are critical though and impact the quality.
The last thing you can do is to visually check the website in all modern browsers such as Chrome, Firefox, IE 8+ and Safari. If you don’t have access to all this browsers here is a tool that can help out: http://browsershots.org/
If you’re building a new website, it is a great strategy to build a Coming Soon page with few keywords within Title tag and some excerpt content. That way Google and other search engines can index your website early in the process and you can get an head start.
Here are some points to consider so you can avoid penalization and optimize everything at the best after the website is ready:
This is all new but it will make your website more social friendly. For example you can specify which image and what description text will show up when somebody shares your page on the Facebook timeline. By default is auto generated and you’ll want to control that.
While social media might not be applicable to every site, for those who want to promote on social networks, this is a great way to do it and it is easy to implement. Just ask your developer to add few meta tags within thesection and you’re good to go.
Here is a link where you can learn more about implementation: http://ogp.me.