I stayed at the Le Meridien in Singapore over Christmas on a Priceline.sg stay, and it was SG$107+taxes per night, so not too shabby. Apart from priceline, the website I've found with consistently good prices is
www.asiarooms.com - considering they're prices including tax, and often with breakfast too they can be pretty good value.
As for other recommendations, well I've stayed at far too many 3-5* places in Singapore (mostly around the 4* level) and most of them are pretty similar overall. Ones I'd stay in again include the Conrad (which used to have a great weekend rate, but no longer seems to offer it), the Swissotel Stamford, Hotel Rendezvous and Berjaya Duxton, depending on the prices on offer and which area of Singapore I was in the mood for staying in. Others I've stayed in, including the Plaza Parkroyal, Allson, Riverview, Hotel Phoenix and New Park Hotel have all been fine enough, and would go back to if other options weren't available, but wouldn't be rushing back to anytime soon either (and most are poorly located, apart from the Hotel Phoenix).
I'll agree the Intercontinental has nice rooms (the one I stayed in was pleasant enough), but wasn't particuarly impressed by the service - then again as a youngish traveller (who had a backpack firmly attached when arriving) perhaps I wasn't quite the demographic they were looking to cater to. Even worse was the Pan Pacific, again the rooms were nice, but the service was pretty ordinary, and had a number of issues with the bill on checking out. The Peninsula/Excelsior hotel seemed to *always* have long queues for checking in and checking out when I stayed there, and the rooms were pretty average, so I'd say spending $10 a night more somewhere else would be worth your while if on the lower end of the budget.
Personally I'd like to try the Gallery at some stage, especially with its proximity to nightlife being a bonus. The Scarlet Hotel -
www.thescarlet.com looks interesting too, I'd be happy to hear if anyone has stayed there yet? Otherwise for more of a budget option, Hangout at Mt.Emily -
www.hangouthotels.com looks inviting, especially for the price it seems a bit of a bargain!