Since September 2016, when Myanmar increased their Visa fees, they have also restrict the Visa-On-Arrival only for those traveling to the country for Business purposes (you will also have to provide the supporting documents included an invitation letter from the company in Myanmar registered with the Myanmar Foreign Investment Commission and a recommendation letter from the company the business traveller was employed with). By raising the prices, the immigration ministry aims to bring visa fees in line with other countries, which generally charge more than Myanmar. The rise in fees affects 12 types of visas, not including diplomatic visas, which will remain free of charge.

This is listed in the e-visa website's FAQ.

But the silver lining in this is that the e-visa system is quite reliable (but remember to turn off your pop-up blocker before visiting the site). If you don't want to use the e-visa system, you can also walk in to the Myanmar embassy.

Only exception to this rule regarding the visa status is if you're a Singaporean. Since Dec 1 (2016), Singaporeans travelling to Myanmar for short trips will no longer need to apply for a visa. Myanmar nationals visiting Singapore will also not have to apply for a Singapore visa under a 30-day visa exemption announced on June 7, 2016.

Under the agreement, both countries will grant an exemption of visa to each other's citizens for a stay of not longer than 30 days, and subject to prevailing entry requirements. The arrangement applies to those holding ordinary passports, and will be implemented by both sides on Dec 1 (2016). The announcement of the visa exemption is part of a growing relationship between both countries.

So before you think you can just pop over to Myanmar whenever you want, apply ahead of time before you buy your air tickets or you'd be in for a rude surprise when you reach the airport and get stopped before you even step out of the airport.

Will update this if there's any changes to the status, especially for Malaysians wanting to visit Myanmar.